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SERVICE MANUAL VL BOILER BASE SERIES CONVECTION STEAMERS (GAS, ELECTRIC, DIRECT AND REGENERATED) VL2GPS SHOWN VL2GPS ML-52391 VL2DPS ML-52749 VL2GMS ML-52388 VL2DMS ML-52750 VL2GAS ML-52390 VL2DAS ML-52751 VL2GSS ML-52389 VL2DSS ML-52752 VL3GPS ML-52395 VL3DPS ML-52753 VL3GMS ML-52392 VL3DMS ML-52754 VL3GAS ML-52394 VL3DAS ML-52755 VL3GSS ML-52393 VL3DSS ML-52756 VL2EPS ML-52741 VL2RPS ML-52757 VL2EMS ML-52742 VL2RMS ML-52758 VL2EAS ML-52743 VL2RAS ML-52759 VL2ESS ML-52744 VL2RSS ML-52760 VL3EPS ML-52745 VL3RPS ML-52761 VL3EMS ML-52746 VL3RMS ML-52762 VL3EAS ML-52747 VL3RAS ML-52763 VL3ESS ML-52748 VL3RSS ML-52764 - NOTICE This Manual is prepared for the use of trained Vulcan Service Technicians and should not be used by those not properly qualified. If you have attended a Vulcan Service School for this product, you may be qualified to perform all the procedures described in this manual. This manual is not intended to be all encompassing. If you have not attended a Vulcan Service School for this product, you should read, in its entirety, the repair procedure you wish to perform to determine if you have the necessary tools, instruments and skills required to perform the procedure. Procedures for which you do not have the necessary tools, instruments and skills should be performed by a trained Vulcan Service Technician. Reproduction or other use of this Manual, without the express written consent of Vulcan, is prohibited. A product of VULCAN-HART Form 24650 (May 1999) LOUISVILLE, KY 40201-0696 VL SERIES STEAMERS TABLE OF CONTENTS GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Compartment Pan Capacity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Model Designations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Water Conditioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Water Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Steam Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Gas Steamers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Electric Steamers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Steamer Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Gas Powered Steam Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Electrically Powered Steam Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Regenerated Steam Powered Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Direct Steam Powered Cooker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Boiler Blowdown and Steamer Shut off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Cooking Compartment Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Component Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Cabinet Base Boiler Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Cooking Compartment Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 REMOVAL AND REPLACEMENT OF PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Component Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Water Level Controls - Low Level Cut off and Differential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Water Level Gauge Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cycling and High Limit Pressure Switches (Gas and Electric Models) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Boiler Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High Limit Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Boiler Fill and Cold Water Condenser Solenoid Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pilot and Thermocouple Assembly (Gas Models) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gas Combination Control Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Compartment Gasket and Door Screw Nut, Door and Bushings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Heater Contactors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Heating Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Regenerated Steam Models (Steam Coil) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SERVICE PROCEDURES AND ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Clean-out (All Boiler Models) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Deliming Only (Models with Deliming Port Assembly) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Descaler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Water Level Control(s) Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cycling and High Limit Pressure Switches (Gas and Electric Models) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fill and Cold Water Solenoid Valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Compartment Pressure Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . High Limit Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Boiler Not Filling with Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Boiler Blowdown Drain Solenoid Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Boiler Slow to Pressurize . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inlet Water Strainer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pilot and Thermocouple Assembly (Gas Models) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gas Burners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Air Shutter Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic Ignition Systems (Gas Models) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gas Manifold Pressure Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page 2 of 88 14 14 17 17 17 18 18 19 19 19 20 21 21 21 22 22 22 22 23 23 24 25 26 26 27 27 27 28 29 29 31 31 31 31 33 VL SERIES STEAMERS Direct Steam Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Regenerated Steam (Older Models) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Heater Contactors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Heating Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Thermal Switch - Prevent and Automatic Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Water Level Gauge Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Steam Gate Valve(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 34 34 34 36 36 37 ELECTRICAL OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Water Level Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Solid State - Low Level Cut-off & Differential Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electro Mechanical - Low Level Cut-off & Differential Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sequence of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gas Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electric Models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Schematics, Gas Steamers, Boiler Controls VL2G AND VL3G - Prevent, Automatic, Standard and Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual Ignition, Standard Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electronic Ignition, Standard Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual Ignition, Csd-1 Code Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electronic Ignition, Csd-1 Code Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Wiring Diagrams, Gas Steamers, Boiler Controls VL2G AND VL3G - Prevent, Automatic, Standard and Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual Ignition, Standard Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electronic Ignition, Standard Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual Ignition, Csd-1 Code Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electronic Ignition, Csd-1 Code Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Schematics, Electric Steamers, Boiler Controls VL2E AND VL3E - Prevent, Automatic, Standard and Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto Blowdown, Standard Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto Blowdown, Cal-code Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Wiring Diagrams, Electric Steamers, Boiler Controls VL2E AND VL3E - Prevent, Automatic, Standard and Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto Blowdown, Standard Controls (Contactor - 1 Std.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Auto Blowdown, Standard Controls (Contactors - 2 Std.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual Blowdown, Cal-code Controls (Contactors - 1 Std. 1 Aux.) . . . . . . . . . . . . . . . . . . . . . . Auto Blowdown, Cal-code Controls ( Contactors - 1 Std. 1 Aux.) . . . . . . . . . . . . . . . . . . . . . . . . Auto Blowdown, Cal-code Controls (Contactors - 2 Std. 2 Aux.) . . . . . . . . . . . . . . . . . . . . . . . . Manual Blowdown, Cal-code Controls (Contactors - 2 Std. 2 Aux.) . . . . . . . . . . . . . . . . . . . . . . Wiring Diagrams, Electric Heater Circuits VL2E AND VL3E - Prevent, Automatic, Standard and Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Schematic and Wiring Diagrams, Direct Steamers, Cabinet Base VL2D AND VL3D - Prevent, Automatic, Standard and Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Wiring Diagrams, Regenerated Steamers, Boiler Controls VL2R AND VL3R - Prevent, Automatic, Standard and Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Schematic and Wiring Diagrams - Compartment Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Prevent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 38 38 40 42 42 45 49 49 50 51 52 54 54 56 58 60 62 62 63 64 64 66 68 70 72 74 76 77 78 80 80 81 82 83 TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 © VULCAN 1999 Page 3 of 88 VL SERIES STEAMERS - GENERAL GENERAL Boiler Code Descriptions INTRODUCTION Steam Cooking Large capacity pressure steamers offer an efficient way to produce a wide variety of foods in small portions or larger batches. Steamers can be used to cook fresh foods, blanch foods for complete cooking later or will steam defrost and cook frozen foods. Cooking with steam assures the food will retain its maximum color, flavor and nutritional value with the least expenditure of energy and labor. Compartment Pan Capacity PANS PER COMPARTMENT SIZE DEPTH (INCHES) 4 12" x 20" 6.0 6 12" x 20" 4.0 8 12" x 20" 2.5 6 *18" x 20" 1.0 * Remove center support for 18x20 inch pans Model Designations Vulcan-Hart incorporates redundant controls in compliance with California Code (Cal-Code) and CSD-1 as an option on steam equipment when required by state and/or local building code requirements. Descriptions of the codes are listed below. Cal-Code Construction - Redundant controls in the electrical safety circuits that, if tripped, must manually be reset after the condition causing the trip subsides. These controls consist of one dual function water level cycling and low level cut off control and one single function low water level cutoff control (Aux - LLCO) and a high pressure relief switch in conjunction with a mechanical pressure relief valve. CSD-1 Construction - Redundant controls in the electrical safety circuits that, if tripped, must manually be reset after the condition causing the trip subsides. These controls consist of one dual function water level cycling and low level cut off control and one single function low water level cutoff control (LLCO) and a high pressure relief switch in conjunction with a mechanical pressure relief valve. Additionally, both circuits have individual indicator lights that will illuminate for a visual verification of the shutdown mode. Cal-Code and CSD-1 construction both require operator intervention in the event of a shutdown. CSD-1 is more informative by using indicator lights to show which safety system was shutdown. V L X X XX Cooking Control Types: PS - Prevent Steam AS - Automatic Steam SS - Standard Steam MS - Manual Steam Heating System: G - Gas E - Electric D - Direct R - Regenerated Number of Compartments Large Capacity Pressure Steamer Vulcan WATER CONDITIONING Furnishing the boiler with soft water to reduce scale formation is important. Scale formation will reduce steam output, cause premature component failure, and shorten equipment life. Most water supplies contain scale producing minerals such as Calcium and Magnesium. As steam is generated, the minerals remain and dissolve into the water. As the concentration of these minerals increases past a certain point, they precipitate from the water and coat the inside of the boiler, heating elements, thermostat bulbs and water level probes. Because of the high temperature of these surfaces, the precipitated minerals bake onto them and become very difficult to remove. Page 4 of 88 VL SERIES STEAMERS - GENERAL This causes several problems: 1. Reduce the heat transfer efficiency of the heating system. 2. Cause premature failure of Electric heaters. 3. Water level probes will give false readings. 4. Thermostat bulbs will sense temperature incorrectly. NOTE: Adaptors vary between manufacturers. An example of one adaptor type is pictured below. These problems are common to any manufacturer's steamer regardless of design, but they can all be prevented by furnishing the boiler with soft water. Vulcan recommends the water contain less than 60ppm of “total dissolved solids” (TDS) and have a PH factor between 7 to 8. These water properties can be achieved by using a properly maintained water softener. Other chemical properties in water supplies can also affect good steam generation and vary from within each state and locality. The water level probes in the boiler use ions in the water to detect the water level. Do not use fully demineralized or de-ionized water since it is "non conductive" and the water level can not be detected. NOTE: The use of strainers, or filters will not remove minerals from the water. Vulcan recommends that a local water treatment specialist be consulted before the installation of any steam generating equipment. Steamers that operate over a long period of time without the benefit of a water softener, which have developed a heavy scale build up, should be cleaned before using a water softener. TOOLS SPECIFICATIONS Water Supply Supply pressure should be In line strainer for supply line Supply connection Total dissolved solids (TDS)* Total alkalinity Silica Chloride PH factor (*17.1 ppm = 1 grain of 20-80 psig (Not Supplied) cold less than 60 ppm less than 20 ppm less than 13 ppm less than 30 ppm 7 to 8 hardness) Steam Supply Dry steam must be provided to the steamer for suitable use. If the steam is heavy with condensate, a Ball Float Trap must be used in the line and plumbed in before the pressure reducing valve. To ensure rapid heat up of heavy cold loads, the steam supply line must be sized to maintain pressure as outlined below. Standard Standard set of hand tools. Volt-Ohm-Meter (VOM) with AC current tester. (Any quality VOM with a sensitivity of at least 20,000 ohms per volt can be used) Gas leak checking equipment. Gas pressure manometer CLR Treatment Kit - Used to remove Calcium/Lime/Rust from a boiler (Contact Vulcan Authorized Service Centers ). Adaptor to test thermocouple closed circuit voltages (DC) on gas models with manual ignition (purchase locally). REGENERATED STEAMERS - (POTABLE) OLDER MODELS (*NON-POTABLE) Supply Pressure Input 15 psi (min.) 15 psi (min.) Flow Rate 50 lb. per hour per compartment 125 lb. per hour Pressure Reducing Valve Output 10 psi (furnished) Temperature meter and thermocouple. Special DIRECT STEAM STEAMERS set accordingly for good steam generation (1012psi) *Potable steam is not required for regenerated models but could be used. Page 5 of 88 VL SERIES STEAMERS - GENERAL Gas Steamers LINE PRESSURE MANIFOLD PRESSURE INPUT (BTU/HR) (INCHES W.C.) AMPS (INCHES W.C.) NATURAL LOAD PROPANE (WATTS) MAX MODEL NAT. PROP. 200,000 200,000 240,000 240,000 200,000 200,000 240,000 240,000 200,000 200,000 240,000 240,000 200,000 200,000 240,000 240,000 200,000 200,000 240,000 240,000 200,000 200,000 240,000 240,000 200,000 200,000 240,000 240,000 200,000 200,000 240,000 240,000 VL2GPS VL2GMS VL2GAS VL2GSS VL3GPS VL3GMS VL3GAS VL3GSS PROP. RECOMMEND MIN RECOMMEND MIN 4.0 10.0 7.0 5.0 11.0 11.0 14.0 360 3.0 4.0 10.0 7.0 5.0 11.0 11.0 14.0 360 3.0 4.0 10.0 7.0 5.0 11.0 11.0 14.0 360 3.0 4.0 10.0 7.0 5.0 11.0 11.0 14.0 360 3.0 4.0 10.0 7.0 5.0 11.0 11.0 14.0 360 3.0 4.0 10.0 7.0 5.0 11.0 11.0 14.0 360 3.0 4.0 10.0 7.0 5.0 11.0 11.0 14.0 360 3.0 4.0 10.0 7.0 5.0 11.0 11.0 14.0 360 3.0 AMPERAGE 1 PHASE TOTAL KW 24* 3 PHASE 3 PHASE - 4 WIRE 208V 240V 208V 240V 480V 220/380V & 240/415V 116 100 67 58 29 34 36 100 87 44 50 42 117 116 58 67 67 58 29 34 36 100 87 44 50 42 117 116 58 67 67 58 29 34 36 100 87 44 50 42 117 116 58 67 67 58 29 34 36 100 87 44 50 42 117 116 58 67 VL2EPS 48 24* VL2EMS 116 100 48 24* 116 100 VL2ESS 48 24* 116 100 VL2EAS 48 120V NAT. Electric Steamers MODEL (MAX) *std Page 6 of 88 60HZ VL SERIES STEAMERS - GENERAL Also, the ignition control module ON/OFF/RESET switch must be in the ON position to operate. This switch is located on the upper left side of the electrical control box for the ignition control module. A red light will illuminate when the switch is in the ON position. DO NOT ATTEMPT TO MANUALLY LIGHT THE PILOT IN AN AUTOMATIC TYPE IGNITION SYSTEM. STEAMER OPERATION Ensure that all utility connections to the steamer have been made and are turned on. On models that are CSD-1 equipped, amber colored lights for hi pressure and low water level will illuminate and stay on until the boiler is full and the manual reset switch pressed. After the main power switch is turned ON and the ignition control modules RESET switch is in the ON position, sparking will begin three seconds later to light the standing pilot. If the pilot lights, a signal is sent back through the ignition cable indicating the presence of pilot flame and sparking stops. If the water level in the boiler has reached the minimum level, the burners will ignite and begin to heat the water in the boiler. After approximately 15 minutes, steam should be present for cooking product. Observe that the boiler pressure gauge indicates a steam pressure of 9-11 psi for models with a pressure regulating valve or 4-6 psi for models without the valve. If a pilot flame is not established immediately, sparking will continue for 90 seconds. After that duration, the ignition control module will lock out and needs to be reset to start the pilot and burner lighting cycle again. Gas Powered Steam Boiler 5. Open the cabinet door and turn main power switch ON. The red light will illuminate, water will begin filling the boiler and the blowdown solenoid valve will close. The boiler should fill, in four to eleven minutes. Observe water level gauge glass to verify that water is in boiler and that the level in the gauge glass is about half full. Both valves on gauge glass assembly must be open to fill the gauge. Older models equipped with a manual “ball” type blowdown valve must be closed for the boiler to fill. The cycling pressure switch will maintain the proper steam pressure in the boiler by cycling the heating system on and off to generate steam pressure. A. On Models with Manual Ignition - The knob on the gas combination control valve has three positions (On-Pilot-Off) for control of main burners and pilot. Turn knob on gas combination valve to PILOT then depress and light pilot burner with a lit taper. Maintain knob in depressed position for about 30 seconds and release. Observe that pilot burner flame stays on. If the flame should go out, wait 5 minutes before relighting. Turn knob on gas combination control valve to ON. If the water level in the boiler has reached the minimum level, burners will ignite and begin to heat the water in the boiler. After approximately 15 minutes, steam should be present for cooking product. Observe that the boiler pressure gauge indicates steam pressure of 9-11 psi for models with a pressure regulating valve or 4-6 psi for models without the valve. B. On Models with Automatic Ignition The knob on the gas combination control valve has two positions (On-Off) for control of main burners and pilot. For the automatic ignition system to work, the knob must be set in the ON position or gas for the pilot and main burners will not flow. Electrically Powered Steam Boiler Open the cabinet door and turn main power switch ON. The red light will illuminate, water will begin filling the boiler and the blowdown solenoid valve will close. The boiler should fill, in approximately 11 minutes. Observe water level gauge glass to verify that water is in boiler and that the level in the gauge glass is about half full. Both valves on gauge glass assembly must be open to fill the gauge. Older models equipped with a manual “ball” type blowdown valve must be closed for the boiler to fill. If the water level in the boiler has reached the minimum level, the heater contactors will close, the heaters will energize and begin to heat the water in the boiler. After approximately 15 minutes, steam should be present for cooking product. Observe that the boiler pressure gauge indicates steam pressure of 9-11 psi for models with a pressure regulating valve or 4-6 psi for models without the valve. Regenerated Steam Powered Boiler Open the cabinet door and turn main power switch ON. The pilot light will illuminate, water will begin filling the boiler and the blowdown solenoid valve will close. Models equipped with a manual “ball type” blowdown valve need to be closed for the boiler to fill. The boiler should fill, in approximately 15 minutes. Page 7 of 88 VL SERIES STEAMERS - GENERAL Observe water level gauge glass to verify that water is in boiler and that the level in the gauge glass is about half full. Both valves on the gauge glass assembly must be open to fill the gauge. When the water reaches the minimum level, the steam solenoid valve will open, allowing steam to enter the steam coil in the heat exchanger tank and begin heating the water. After approximately 20 minutes, a sufficient amount of pressurized steam should be present for cooking product. Direct Steam Powered Cooker 1. 2. Cooking Compartment Controls Close the compartment door and turn the screw handle clockwise until the gasket touches the compartment surface then ½ turn further to adequately seal the compartment. If steam leaks occur after compartment heat up and pressurization, turn handle clockwise again to increase the sealing force until the leak stops. Proceed to the cooking compartment control instructions that apply to the steamer in use. 1. Open the cabinet door and turn main power switch ON. A. The red light on the switch will illuminate. B. If steam pressure is above the minimum setting on the cooking compartment pressure switch then the switch will close, ready light will come ON and power to the other controls will be supplied. C. Observe that the steam pressure gauge in the cabinet base, indicates 10-12 psi. Manual A. Set the manual timer to the desired cooking time. If preheating is desired, allow five to ten minutes (recommended) of additional time at the beginning of the cook cycle. The length of time will vary with the type, size, temperature and condition (frozen or thawed) of the product and must be determined from experience. Pull the steam control arm handle forward and lock it by pulling the handle down. This closes the steam exhaust gate valve and opens the steam inlet gate valve, allowing steam to enter the compartment. During preheat, cooler air and condensate are exhausted from the compartment through the steam trap (condenser) until the temperature reaches 180°F, closing the internal bellows. Throughout the cooking cycle, the compartment pressure should be 6 psi if equipped with a compartment pressure regulating valve. On models without the compartment pressure regulating valve, the compartment pressure cycles with the boiler pressure between 4 and 6 psi. B. When the timer bell rings to signal the end of a cook cycle, turn it OFF. Lift the steam control arm handle to unlatch team control arm. An internal spring will automatically pull the arm to the rear. This closes the steam inlet gate valve and opens the steam exhaust gate valve, allowing steam and pressure to exit the compartment. C. Wait approximately 30 seconds for the steam to exhaust from the compartment and to depressurize. Turn the screw handle on the compartment door counterclockwise until the gasket no longer seals against the compartment surface. After the remaining steam escapes, move the latch paddle to the left and open the door. Steamer is ready to cook product. Boiler Blowdown and Steamer Shut off Turn the steamer off at least once daily and blow down the boiler to remove sediments, scalants and lime build-up in the boiler. Always blowdown the boiler when it is under maximum pressure and no steam is being used. 3. Automatic blowdown. A. B. 4. Newer Models - Open the cabinet door and turn main power switch OFF. The switches’ red light will go out, the blowdown/drain solenoid valve will be deenergized and the boiler will begin to drain. The cold water condenser solenoid will continue to operate, as needed, to condense steam and to cool the water going into the drain. Older Models - Turn power switch OFF and depress blowdown timer button. Blowdown timer will operate for 4 minutes. At the end of blowdown, turn fill switch ON and allow boiler to fill. Manual blowdown. A. All Models - Turn power switch OFF. Open blowdown valve located on the bottom front of the cabinet base. After the boiler has completely drained, close blowdown valve and turn fill switch to ON and allow boiler to fill. Page 8 of 88 VL SERIES STEAMERS - GENERAL 2. Standard A. 3. Set the timer to the desired cooking time. The timer must be set past five minutes to change the state of the timer control micro switch contacts. If preheating is desired, allow five to ten minutes (recommended) of additional time at the beginning of the cook cycle. The length of time will vary with the type, size, temperature and condition (frozen or thawed) of the product and must be determined from experience. B. Pull the steam control arm handle forward and lock it by pulling the handle down. This closes the steam exhaust gate valve and opens the steam inlet gate valve, allowing steam to enter the compartment. C. Press the compartment power switch to energize the timer and red light. The balance of the cooking sequence is automatic. During preheat, cooler air and condensate are exhausted from the compartment through the steam trap (condenser) until the temperature reaches 180°F, closing the internal bellows. Throughout the cooking cycle, the compartment pressure should be 6 psi if equipped with a compartment pressure regulating valve. On models without the compartment pressure regulating valve, the compartment pressure cycles with the boiler pressure between 4 and 6 psi. D. Approximately one minute before timer reaches zero the steam control solenoid is energized to unlatch the steam control arm. An internal spring will automatically pull the arm to the rear. This closes the steam inlet gate valve and opens the steam exhaust gate valve, allowing steam and pressure to exit the compartment. When the timer reaches "0" the red light shuts off and a buzzer sounds indicating the end of the cook cycle. Turn the compartment power switch OFF to silence the buzzer and remove power from the compartment controls. E. Turn the screw handle on the compartment door counterclockwise until the gasket no longer seals against the compartment surface. After the remaining steam escapes, move the latch paddle to the left and open the door. Page 9 of 88 Automatic A. Set the timer to the desired cooking time. The timer must be set past five minutes to change the state of the timer control micro switch contacts. B. Pull the steam control arm handle forward and lock it by pulling the handle down. This closes the steam exhaust gate valve and opens the steam inlet gate valve, allowing steam to enter the compartment. C. Press the compartment power switch to supply power to the compartment controls. The automatic compartment controls, feature load compensated cooking time by utilizing a thermal switch. With this feature, when the compartment temperature reaches 180°F (the temperature at which preheating or defrosting is complete) the red light will then come on and the timer will start. For a small food load, the delay time before the timer starts might be a minute or less. For a large food load, the delay time could be four to five minutes. During preheat, cooler air and condensate are exhausted from the compartment through the steam trap (condenser) until the temperature reaches 180°F, closing the internal bellows. Throughout the cooking cycle, the compartment pressure should be 6 psi if equipped with a compartment pressure regulating valve. On models without the compartment pressure regulating valve, the compartment pressure cycles with the boiler pressure between 4 to 6 psi. D. Approximately one minute before timer reaches zero the steam control solenoid is energized to unlatch the steam control arm. An internal spring will automatically pull the arm to the rear. This closes the steam inlet gate valve and opens the steam exhaust gate valve, allowing steam and pressure to exit the compartment. When the timer reaches "0" the red light shuts off and a buzzer sounds indicating the end of the cook cycle. Turn the compartment power switch OFF to silence the buzzer and remove power from the compartment controls. E. Turn the screw handle on the compartment door counterclockwise until the gasket no longer seals against the compartment surface. After the remaining steam escapes, move the latch paddle to the left and open the door. VL SERIES STEAMERS - GENERAL 4. Prevent A. Set the timer to the desired cooking time. The timer must be set past five minutes to change the state of the timer control micro switch contacts. B. Pull the steam control arm handle forward and lock it by pulling the handle down. This opens the steam inlet gate valve, allowing steam to enter the compartment. C. Press the compartment power switch to supply power to the compartment controls. The prevent compartment controls feature load compensated cook times by utilizing a thermal switch. With this feature, when the compartment temperature reaches 180°F (the temperature at which preheating or defrosting is complete) the red light will come on and the timer will start. For a small food load, the delay time before the timer starts might be a minute or less. For a large food load, the delay time could be four and five minutes. During preheat, the steam exhaust solenoid valve (N.O.) is open to allow the full free venting of cooler air and condensate from the compartment. When the temperature reaches 180°F, the exhaust solenoid valve is energized and closes. The compartment should then pressurize to 6 psi. Page 10 of 88 D. Approximately one minute before timer reaches zero the steam control solenoid is energized to unlatch the steam control arm. An internal spring will automatically pull the arm to the rear. This closes the steam inlet gate valve and opens the steam exhaust gate valve, allowing steam and pressure to exit the compartment. When the timer reaches "0" the red light shuts off and a buzzer sounds indicating the end of the cook cycle. Turn the compartment power switch OFF to silence the buzzer and remove power from the compartment controls. E. Turn the screw handle on the compartment door counterclockwise until the gasket no longer seals against the compartment surface. After the remaining steam escapes, move the latch paddle to the left and open the door. VL SERIES STEAMERS - GENERAL COMPONENT FUNCTION CABINET BASE BOILER CONTROLS Water Level Gauge Assembly . . . . . . . . . . . . . . . Water Level Control and Level Sensing Probes . . . . . . . . . . . Boiler Fill Solenoid Valve . . . . . . . . Cold Water Condenser Solenoid Valve . . . . . . . . . . . . . . . . . Permits a visual confirmation the water level is being maintained in boiler during operation. The correct water level is a point one-half of the height of the glass. The manual valves at the top and bottom of this assembly must be fully open and only closed if the glass tube is damaged. These controls allow water to enter the boiler to fill and maintain the proper water level. They will also shut off the heat source to the boiler if the water level drops too low. The water level control works by using three different probe lengths to monitor the water level. The probes consist of a high level (HL), low level (LL) and low water cut-off (LLCO). Admits water to the boiler when demanded by the water level control to maintain the correct water level in the boiler. Allows cold water flow into the boiler blowdown drain box to condense steam and cool the hot water before its discharge into the drain. Cycling Pressure Switch . . . . . . . . . Controls boiler pressure between prescribed limits by turning the heat source on and off. High Limit Pressure Switch . . . . . . A switch of identical design to the cycling pressure switch but used as a high limit. The pressure settings are at higher and lower limits than the cycling pressure switch in order to turn off the heat source before the boiler pressure reaches its limit and automatically resets after the pressure drops below the lower limit set point. Blowdown/Drain Solenoid Valve . . . . . . . . . . . . . . . . . This valve is plumbed into the drain line of the boiler. Newer steamer models will automatically blowdown when power is turned off by using a normally open solenoid valve. Older models can have a solenoid valve that is activated by depressing a separate blowdown timer button or have a manual “ball” type valve. Inlet Water Strainer . . . . . . . . . . . . . A strainer is used in the water inlet line to prevent foreign matter from becoming lodged in the fill or cold water condenser solenoid valves and to keep unwanted particles out of the system. A "Y" strainer should be inserted upstream of the fill solenoid valve. On models using a direct steam supply, a strainer is also used in the pressure regulating valve. Power Switch . . . . . . . . . . . . . . . . . . When turned ON, power is supplied to the controls and the steam generating process is started in the boiler. The power switch is located on the front of the boiler control box. Water Inlet Valve . . . . . . . . . . . . . . . The water inlet valve is used to stop water flow to the steamer when the steamer is being serviced. Newer models will have a small Petcock type valve while older models will be a “ball” type valve. This valve should remain open during normal operation. High Limit Thermostat . . . . . . . . . . A protective device that shuts off the heat source if the boiler temperature exceeds a specified limit. All standard models are equipped with a surface high limit. Descaler . . . . . . . . . . . . . . . . . . . . . . Hangs submerged in water inside the boiler and is used to help control boiler surface scaling. Two descalers are used in each boiler. Page 11 of 88 VL SERIES STEAMERS - GENERAL Handhole Cover Assembly . . . . . . . When unbolted and removed, allows internal examination and cleaning of boiler shell and its components if required. Boiler Pressure Gauge . . . . . . . . . . Indicates the amount of steam pressure in the boiler. Check Valve . . . . . . . . . . . . . . . . . . . On models with the delime piping assembly option, prevents the ejection of hot water and steam out of the delime funnel if the manual delime fill valve were to be opened. Delime Port Assembly . . . . . . . . . . . On models with the delime piping assembly option, allows the boiler and other internal components to be delimed, easily removing calcium, lime and rust build up. Gas Pilot . . . . . . . . . . . . . . . . . . . . . Should always remain lit to light the main burners upon a call for heat unless the steamer will not be in use for an extended period. If the pilot flame goes out, wait 5 minutes before relighting. Gas Burners . . . . . . . . . . . . . . . . . . . Heats the water in the boiler to generate steam. Gas Combination Control Valve . . . A gas solenoid valve that opens to allow gas flow when a call for heat is made. Also regulates the manifold gas pressure and supplies the gas pilot. Transformer . . . . . . . . . . . . . . . . . . . Provides 24VAC power to ignition control module. (gas models with electronic ignition) Ignition Control Module . . . . . . . . . Controls and monitors gas heating. Energizes pilot valve coil to supply gas to pilot, generates spark to ignite gas at the pilot, monitors the presence of flame and energizes main valve coil upon a call for heat to supply gas to the main burners. The pilot and main solenoids are part of the gas combination control valve. (gas models with electronic ignition) Ignition Control Module Reset (ON/OFF) Switch . . . . . . . . . . Controls power to the ignition control module and allows a reset of the module if the gas ignition exceeds trial time. (gas models with electronic ignition) Heater Contactor (Electric Boilers) . . . . . . . . . . . . . . . When coil is energized, supplies power to the electric heating elements. Heating Elements (Electric Boilers) . . . . . . . . . . . . . . . Heats the water in the boiler to generate steam. Steam Header Assembly . . . . . . . . . Main steam supply line from the boiler to the steam header inlet in the cooking control compartment. Pressure Relief Valve . . . . . . . . . . . A mechanical device that opens to relieve steam pressure in the boiler if the pressure exceeds 15 psi. Compartment Pressure Regulating Valve . . . . . . . . . . . . . . . Reduces steam pressure form the boiler or building steam (direct and regenerated models) to supply the compartments a steam pressure of 6 psi. Standard on PS, option on MS, SS and AS compartment controls. Page 12 of 88 VL SERIES STEAMERS - GENERAL COOKING COMPARTMENT CONTROLS The top half of the steamer consists of two to three separate cooking compartments depending on the model. Each compartment functions independently with its own set of controls. Power is supplied to the controls through the compartment power switch and the cooking timer control micro switch contacts. Prevent and Automatic models have a load compensating thermal switch that prevents the controls from receiving power until the compartment reaches 180°F to close the switch. Compartment Power Switch . . . . . . Supplies power to the cooking compartment controls. Cooking Light (Red) . . . . . . . . . . . . When lit, indicates steamer is in a cooking cycle. (All models except manual) Cooking Timer . . . . . . . . . . . . . . . . . Use to set desired cooking cycle time between 0-60 minutes. Energizes the buzzer when time expires (All models except manual). On Prevent models, also de-energizes the steam exhaust solenoid valve one minute before the end of a cook cycle to allow compartment venting. Buzzer . . . . . . . . . . . . . . . . . . . . . . . Signals end of a cook cycle, must be turned off manually. (All models except manual) Steam Exhaust Solenoid Valve . . . A normally open valve that allows full compartment venting of air and condensate up to 180°F during compartment heat up and “limited free venting” after energized by the closing of the thermal switch. The valve remains closed to allow compartment pressurization to 6 psi until one minute before the end of a cook cycle at which point the timer control micro switch contacts (SW2) change state and de-energize the valve to vent the compartment of pressure and steam. (prevent models) Steam Header Inlet (manifold) . . . . Main steam supply line from the boiler for each cooking compartment. Supplies steam to the manual steam gate valves. Compartment Pressure Gauge . . . . Indicates the amount of steam pressure in cooking compartments. Steam Control Arm Solenoid . . . . . When energized, engages the lift arm (plunger) to raise the steam control arm off of the catch, allowing it to return to its rear position. This closes the steam inlet gate valve and opens the steam exhaust gate valve. (prevent, automatic and standard models) Thermal Switch (Load Compensator) . . . . . . . . . . . . Controls power to the preheat cycle components. Turns the cooking light on, energizes the steam exhaust solenoid valve and energizes the cooking timer motor to start timing, after the compartment reaches 180(F. (prevent and automatic models) Steam Gate Valves . . . . . . . . . . . . . Manual valves actuated by the steam control arm. Allows steam to flow into the cooking compartment through the inlet steam gate valve when the arm is in a forward position and exhaust the steam through the exhaust steam gate valve when the arm is at the rear. Prevent models use a steam exhaust solenoid valve to exhaust the steam and a single steam gate valve as the steam inlet. The automatic, standard and manual models use one steam gate valve to exhaust the steam and one additional steam gate valve as the steam inlet. Steam Trap (Condenser) . . . . . . . . . Exhausts air and condensate from compartment during preheat until the compartment temperature reaches approximately 180(F. The bellows then close, stopping the exhaust. (all models except prevent) Page 13 of 88 VL SERIES STEAMERS - REMOVAL AND REPLACEMENT OF PARTS REMOVAL AND REPLACEMENT OF PARTS COMPONENT LOCATIONS Page 14 of 88 VL SERIES STEAMERS - REMOVAL AND REPLACEMENT OF PARTS Page 15 of 88 VL SERIES STEAMERS - REMOVAL AND REPLACEMENT OF PARTS COOKING COMPARTMENT CONTROLS - COMPONENT CONFIGURATIONS 1. Prevent thermal switch, inlet steam gate valve, steam exhaust solenoid (shown above) valve, steam control arm solenoid, timer, buzzer and power switch with light. Does not use a steam trap. 2. Automatic same as prevent except does not include steam exhaust solenoid valve but does include an exhaust steam gate valve and two steam traps. 3. Standard same as automatic except does not include thermal switch. 4. Manual manual and exhaust steam gate valves and a manual timer. Includes two steam traps. Page 16 of 88 VL SERIES STEAMERS - REMOVAL AND REPLACEMENT OF PARTS WATER LEVEL CONTROLS LOW LEVEL CUT OFF AND DIFFERENTIAL WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. 4. Slide the glass tube upwards until the bottom of the tube is clear of the fitting and lift it out. 5. When reinstalling the tube use new sealing washers. Do not over tighten the packing nuts; it could break the gauge glass. 6. Open the top and bottom valves and check for proper operation. CYCLING AND HIGH LIMIT PRESSURE SWITCHES Solid State 1. Open the cabinet base doors. 2. Remove the two screws at the top of the boiler control box and allow cover to drop down. 3. Water level control is mounted on the back side of cover. 4. Disconnect lead wires from the board and remove the water level control. 5. Reverse procedure to install and check for proper operation. (GAS AND ELECTRIC MODELS) WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. 1. Open the cabinet base doors and remove the left side panel. 2. Remove the two screws at the top of the boiler control box and allow cover to drop down. 3. The pressure switches are located at the rear of the box. The pressure switch on the right is the cycling or primary control; the one on the left is the high limit control. They are identical switches, differing only in their settings. Electro Mechanical 1. Open the cabinet base doors. 2. Remove the two screws from the left and right side of the water level control box and lift cover off. 3. Disconnect lead wires from the control being replaced and remove. 4. Remove the cover from the pressure switch being replaced and disconnect the lead wires. 4. Reverse procedure to install and check for proper operation. 5. Disconnect the pressure fittings at the bottom of the switch. 6. Remove the mounting screws on the back side of the control box and lift out the pressure switch. 7. Preset the new pressure switch to the approximate cut-out (off) and cut-in (on) set points before installing. See the boiler pressure chart under “CYCLING AND HIGH LIMIT PRESSURE SWITCHES (GAS AND ELECTRIC MODELS)” in “SERVICE PROCEDURES AND ADJUSTMENTS”. 8. Reverse procedure to install. 9. Adjust the pressure switch(s) final set points as outlined under “CYCLING AND HIGH LIMIT PRESSURE SWITCHES (GAS AND ELECTRIC MODELS)” in “SERVICE PROCEDURES AND ADJUSTMENTS” and check for proper operation. WATER LEVEL GAUGE ASSEMBLY WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. 1. Open the cabinet base doors and remove the right side panel. 2. Close the valve at the top and at the bottom of the gauge assembly. 3. Unscrew the packing nuts at the top and bottom of the glass tube. Page 17 of 88 VL SERIES STEAMERS - REMOVAL AND REPLACEMENT OF PARTS BOILER ASSEMBLY HIGH LIMIT THERMOSTAT WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. WARNING: SHUT OFF THE GAS BEFORE SERVICING THE UNIT. 1. Open the cabinet base doors. 2. Electric models only - for gas models proceed to step 3. WARNING: ALL GAS JOINTS DISTURBED DURING SERVICING MUST BE CHECKED FOR LEAKS. CHECK WITH A SOAP AND WATER SOLUTION (BUBBLES). DO NOT USE AN OPEN FLAME. 1. Blow down the boiler and allow to cool, if necessary. 2. Ensure that all utilities to the steamer are off and disconnected. Drain any excess water from the boiler. 3. Disconnect the steam supply line, power leads and drain lines from the cooking compartment top to the boiler base. 4. Disconnect all plumbing connections and power leads from the components inside the control boxes that would obstruct the removal of the boiler through the front of the base, then remove those control boxes. 5. Disconnect the remaining plumbing and electrical connections from the boiler to the controls. 6. Remove the screws holding the flue and flue collector to the base. 7. Remove the anchor screws holding the boiler to the frame. Slide the boiler forward. The burner box, anchored only by the boiler, must be prevented from sliding forward with the boiler. 8. Reverse procedure to install a new boiler and check for leaks and proper operation. 3. A. Newer Models - are not equipped with a hi limit thermostat but rely on the Hi limit pressure switch instead. B. Older Models - the high limit thermostat is located behind the contactor box cover. On electric boilers with two heating elements, the thermostat is connected to one of the heating element lugs. On electric boilers with four heating elements, the thermostat is located on an aluminum plate between the center pair of elements at the top of the elements. Remove the thermostat lead wires and mounting nuts, replace thermostat and check for proper operation. Gas Models only. A. 4. Page 18 of 88 Remove the thermostat cover which is located on the front of the boiler. Disconnect the thermostat lead wires and remove the nuts securing the high limit thermostat to the boiler surface. Reverse procedure to install and check for proper operation. VL SERIES STEAMERS - REMOVAL AND REPLACEMENT OF PARTS BOILER FILL AND COLD WATER CONDENSER SOLENOID VALVES WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. 1. Turn off the water supply to the steamer. 2. Open the cabinet base doors and remove the two screws at the top of the boiler control box and allow cover to drop down. Both solenoid valves are located side by side near the front of the boiler control box with the boiler fill on the right and the cold water condenser to the left. 3. Disconnect the power lead wires from the solenoid valve being serviced. 4. Disconnect the water lines for the valve being serviced and remove the valve. 5. Reverse procedure to install. PILOT AND THERMOCOUPLE ASSEMBLY (GAS MODELS) WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. WARNING: SHUT OFF THE GAS BEFORE SERVICING THE UNIT. WARNING: ALL GAS JOINTS DISTURBED DURING SERVICING MUST BE CHECKED FOR LEAKS. CHECK WITH A SOAP AND WATER SOLUTION (BUBBLES). DO NOT USE AN OPEN FLAME. 1. Open the cabinet doors to access the pilot and thermocouple assembly. The assembly is located to the right of the center burner and half way back from the front. 2. Disconnect thermocouple and pilot gas supply tubing from the combination control valve. 3. Remove the two screws holding the pilot to its bracket. 4. Replace the thermocouple or pilot assembly and check for proper operation. GAS COMBINATION CONTROL VALVE WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. WARNING: SHUT OFF THE GAS SUPPLY BEFORE SERVICING THE UNIT. WARNING: ALL GAS JOINTS DISTURBED DURING SERVICING MUST BE CHECKED FOR LEAKS. CHECK WITH A SOAP AND WATER SOLUTION (BUBBLES). DO NOT USE AN OPEN FLAME. NOTE: Gas combination control valves are not serviceable and should not be disassembled. Once the problem has been isolated to this control, replace it. Do not attempt to repair the assembly. 1. Open the cabinet base doors and remove the two screws at the top of the boiler control box and allow cover to drop down. 2. Disconnect electrical supply wires and conduit running to the combination control valve. 3. Disconnect the thermocouple lead (if applicable), pilot gas supply tube from control and pipe connections on each side of the control. 4. Reverse procedure to install. 5. Set manifold pressure as outlined under “GAS MANIFOLD PRESSURE ADJUSTMENT” in “SERVICE PROCEDURES AND ADJUSTMENTS”. 6. Check for proper operation. Page 19 of 88 VL SERIES STEAMERS - REMOVAL AND REPLACEMENT OF PARTS COMPARTMENT GASKET AND DOOR SCREW NUT, DOOR AND BUSHINGS 4. Turn screw handle fully counterclockwise and remove from door. 5. Remove screws mounting the pressure bar to the backside of the compartment door. Gasket NOTE: A compression spring is mounted behind each screw. Set aside for reuse. 1. Open the compartment door to be replaced. 6. 2. Remove screws securing the gasket retaining plate to the gasket. Remove screws mounting the door screw nut (bronze) to the backside of the compartment door. 7. Reverse procedure to install and check for proper operation. Door and Bushing 3. Lift the gasket off the inner door plate. 4. Position the new gasket on the inner door plate and reverse procedure to install. 1. Open the compartment door to be replaced. 2. Remove the right side pan support inside the compartment. 3. Remove the four bolts inside the compartment that secure the block hinges to the exterior side of the compartment. CAUTION: Door is extremely heavy and will drop when bolts are removed. NOTE: Damage to the gasket sealing surface, such as nicks or cuts, will cause steam leakage. Door Screw Nut 1. Open compartment door to be serviced. 2. Turn screw handle fully clockwise to extend inner door plate assembly. 3. Lift the inner door plate assembly up, until the mounting pins are out of the holes in the pressure bar and set the assembly aside. 4. At this time, the bushings can be replaced if necessary, by removing the bushings from the pin on each block hinge. 5. Reverse procedure to install and check for proper operation. Page 20 of 88 VL SERIES STEAMERS - REMOVAL AND REPLACEMENT OF PARTS HEATER CONTACTORS REGENERATED STEAM MODELS (STEAM COIL) WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. 1. Open the cabinet base doors, remove the two screws from the contactor box cover and lift cover off. 2. Disconnect the electrical lead wires to the coil and the power supply wires from the contactor being replaced. 3. 4. WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. WARNING: SHUT OFF THE STEAM SUPPLY BEFORE SERVICING THE UNIT. 1. Disconnect pipe unions in the steam supply line to the coils and in the condensate discharge line from the coils. Remove the screws form the base of the contactor and lift out. 2. Remove header that supplies steam to the coils by disconnecting union at each coil. Reverse procedure to install and check for proper operation. 3. Remove coil condensate collection header. 4. Remove bolts securing the coil being replaced and pull coil forward. 5. Clean the mating surfaces of the steam coil flange and the boiler. 6. Reverse procedure to install a new steam coil and gasket. 7. Check steamer for proper operation. HEATING ELEMENTS WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. 1. Open the cabinet base doors, remove the two screws from the contactor box cover and lift cover off. 2. Disconnect the electrical lead wires to the element being replaced. 3. Remove the bolts securing the heating element flange to the boiler and lift the element out. 4. Clean the mating surface of the boiler and install a new flange gasket and heating element. 5. Check for leaks and proper operation. Page 21 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS SERVICE PROCEDURES AND ADJUSTMENTS WARNING: CERTAIN PROCEDURES IN THIS SECTION REQUIRES ELECTRICAL TEST OR MEASUREMENTS WHILE POWER IS APPLIED TO THE MACHINE. EXERCISE EXTREME CAUTION AT ALL TIMES. IF TEST POINTS ARE NOT EASILY ACCESSIBLE, DISCONNECT POWER, ATTACH TEST EQUIPMENT AND REAPPLY POWER TO TEST. NOTE: Boiler water capacities vary between seven to nine gallons for both gas and electric models depending on the boiler size and BTU/KW rating. BOILER Inspection It is recommended the boiler be inspected for excessive scale and lime build up on a quarterly basis. In hard water areas or for steamers heavily used, a more frequent interval should be used. This inspection consists of an internal examination and cleaning of the boiler, an examination of the two hanging descalers, and for lime build up on the water level probes. Also, a check of all boiler controls, including the pressure switches. NOTE: If deliming solution accidently comes in contact with steamer components, lightly rinse off with clean water. Periodic service must be performed as outlined in these procedures. See “WATER CONDITIONING” under “GENERAL”. WARNING: READ AND FOLLOW THE INSTRUCTIONS ON THE CLR BOTTLE. USE PLASTIC OR RUBBER GLOVES TO AVOID SKIN CONTACT. IF CLR LIQUID COMES IN CONTACT WITH THE SKIN, RINSE WITH CLEAN WATER. Clean-Out (All Boiler Models) 1. Turn steamer OFF and drain boiler. 2. Remove hand hole plate and gasket (top front) from the boiler by removing the nut and clamp, then tapping the cover lightly to free it while holding the cover stud. This prevents the cover from dropping into boiler. 3. Remove old descaler retaining springs if present. 4. With a wire brush, or equivalent, dislodge and remove all loose scale from boiler shell. The loose material must be either scooped from the boiler or flushed through the drain. 5. Check probe canister and float valve assembly (regenerated models) for a scale build up and clean as necessary. 6. Check drain hole for obstructions. 7. Inspect the condition of the descalers as outlined in this section and replace if necessary. 8. 9. Mix the deliming solution according to the instructions for the chemical being used. Page 22 of 88 A. Models with Blowdown Timer - Pour deliming solution into boiler shell. Proceed to step 9. B. Models without Blowdown Timer - Turn off the incoming water supply. Turn the power switch ON to close the drain valve. Pour deliming solution into boiler shell. Proceed to step 9. C. Models with Deliming Port Assembly Before pouring deliming solution into boiler, clean the seating surfaces for the hand hole gasket and then install a new gasket. Position the hand hole plate and tighten down. Turn off the incoming water supply. Turn the power switch ON to close the drain valve. Open the deliming assembly valve and pour the deliming solution into the port. Close the deliming assembly valve and proceed to step 10. Clean the seating surfaces for the hand hole gasket and then Install a new gasket. Position and tighten the hand hole plate. VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS 10. Cooking compartment timers are to be in the OFF position. Turn the boiler switch ON and open water valve if necessary. B. 11. Boiler is to operate under pressure for 90 minutes or per the instructions for the chemical in use. Models without Blowdown Timer - Turn off the incoming water supply. Turn the power switch ON to close the drain valve. Open the deliming assembly valve and pour the deliming solution into the port. Close the deliming assembly valve and proceed to step 3. 12. Drain boiler by normal methods. 13. Refill boiler and allow to heat until fully pressurized. 14. Repeat step 13 three times. 15. The steamer is now ready for normal operation. Deliming Only (Models with Deliming Port Assembly) Boiler deliming should be performed on a weekly, bi-weekly or monthly basis, depending on the quality of the local water supply. See “WATER CONDITIONING” under “GENERAL”. On steamers using a water purification system, follow the instructions for that system to delime the boiler. Only use the type of chemical recommended or described in the instructions for deliming with this type of system. 3. Top compartments are to be in the OFF position. Turn the boiler switch ON and open water valve if necessary. 1. Turn steamer OFF and drain boiler. 4. 2. Mix the deliming solution according to the instructions for the chemical being used. Boiler is to operate under pressure for 90 minutes or per the instructions for the chemical in use. 5. Drain boiler by normal methods. NOTE: Boiler water capacities vary between seven to nine gallons for both gas and electric models depending on the boiler size and BTU/KW rating. 6. Refill boiler and allow to heat until fully pressurized. 7. Repeat step 6 three times. NOTE: If deliming solution accidently comes in contact with steamer components, lightly rinse off with clean water. 8. Steamer is now ready for normal operation. A. Models with Blowdown Timer - Open the deliming assembly valve and pour the deliming solution into the port. Close the deliming assembly valve and proceed to step 3. Descaler The descaler is accessible through the hand hole opening. It is a coiled wire wound around a solid cylindrical core, and hangs by an open loop from the shell's horizontal stay rod, about 4 inches from the front of the shell. If the wire is eaten through, or if the core of the descaler is eaten away to half its original size, a new descaler should be installed. To install a new descaler, stretch its wire coil so the descaler hangs with its core completely below the minimum water level in the boiler, but hanging free. The descaler must not contact the bottom of the boiler shell, electric heating elements or regenerating steam coils. Page 23 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS WATER LEVEL CONTROL(S) TEST Loose electrical connections may prevent the heat from coming on or may cause the boiler to overfill. An accumulation of lime scale on or near the water level sensing probes may cause them to retain water (moist) on the probe surface and give a false reading. Also, a cracked or damaged insulator may give a false reading. These conditions may prevent the boiler from filling or cause dry firing. Dry firing will result in damage to the heating elements on electric models or to the boiler on gas or electric models. WARNING: THE FOLLOWING STEPS REQUIRE POWER TO BE APPLIED TO THE UNIT DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES. 5. Once the water level reaches the high level (HL) probe, the inverse latching relay of the board (solid state) should energize and lock through the low level probe (LL) and ILR-1 contacts. With ILR-2 contacts open, the HL relay is de-energized and HL LED goes out. With the HL-3 contacts open, the boiler fill solenoid should de-energize and stop the boiler fill. 6. If water is in the boiler but is not being detected by the water level probes, the probes may need cleaned and/or boiler delimed. See “Water Level Probes” as outlined below for inspecting and cleaning of probes and “BOILER” for a procedure on boiler inspection, clean-out and deliming. 7. Turn the power switch OFF and disconnect the lead wire from each probe. Check the probes as outlined below. A. Solid State - Low level Cut-Off & Differential Control 1. Turn the power switch ON. 2. Ensure that water is filling the boiler. 3. A. Confirm that water supply valve(s) are turned on. B. Observe boiler water level in the water level gauge. If empty, boiler should fill in approximately 11 minutes. Check the voltage across terminals L1 & L2 on the board. Meter should read 120VAC. A. B. C. 4. If voltage is correct then the high level (HL) relay should energize, closing HL-3 contacts and the HL LED should light up. The boiler fill solenoid should then energize and start filling the boiler. Verify boiler fill solenoid valve is receiving 120VAC and water is flowing through it. If boiler fill solenoid is receiving power but no water is flowing, inspect fill solenoid for malfunction or valve for clogged ports. If solenoid is bad or ports can not be cleaned, then replace boiler fill solenoid and check for proper operation. If boiler fill solenoid is not receiving power and the electrical connections have been checked, then the HL relay is not being energized or the HL-3 contacts are not closing. Replace water level control board and check for proper operation. With an ohmmeter, check between the probe terminal and boiler shell. An open circuit should be present when the boiler is empty. If resistance is present, remove and inspect the probes as outlined below under “Water Level Probes”. When the boiler is full of water, a resistance reading should be measurable between the probes and boiler. NOTE: The actual resistance reading will depend on water quality and probe condition. 8. After performing steps 1-5A and verifying the water level control boards operation, if the control is not functioning as described, then replace it and check for proper operation. Electro Mechanical - Low level Cut-Off & Differential Control WARNING: THE FOLLOWING STEPS REQUIRE POWER TO BE APPLIED TO THE UNIT DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES. 1. 2. If boiler is filling properly, when the water level reaches the low level cut-off (LLCO) probe, LLCO relay should energize closing LLCO-2 contacts, heat source should come on (standard models only) and LLCO LED will light. Page 24 of 88 Ensure that water is filling the boiler. A. Confirm that water supply valve(s) are turned on. B. Observe boiler water level in the water level gauge. C. Verify boiler fill solenoid valve is receiving 120VAC and water is flowing through it. Check for correct voltage being applied to the low level and differential water level controls. A. Turn the water supply valve off then turn the power switch ON. Check the input voltage across terminals 1 & 2. Meter should read 120VAC. If voltage is correct proceed to step 2B. If voltage is incorrect, find the source of the problem and repeat this step. VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS B. 3. 4. With the boiler empty, check the voltage across terminals 9 & 10. Meter should read 300 to 350VAC. If voltage is correct proceed to step 3. If voltage reading is approximately 30VAC then the internal contactor is energized but the probes are scaled over and moist and/or have a damaged insulator giving a false reading. See “Water Level Probes“ listed below for inspecting and cleaning and “BOILER” for procedures on boiler inspection, clean-out and deliming. If you do not read any voltage, then contactor coil on the water level control is bad and the control should be replaced. Check for proper operation after replacement. If water is in the boiler but is not being detected by the water level probes, the probes may need cleaned and/or boiler delimed. See “Water Level Probes“ listed below for inspecting and cleaning and “BOILER” for procedures on boiler inspection, clean-out and deliming. Turn the power switch OFF and disconnect the lead wire from each probe. Note the location of the probes and the number of the wire connected to it. A. Check the resistance between the probe terminal and boiler shell. An open circuit should be present when the boiler is empty. If resistance is present, remove and inspect the probes as outlined below under “Water Level Probes”. A resistance reading should only be measurable between the probes and boiler shell (ground) when the boiler is full of water. NOTE: The actual resistance reading will depend on water quality and probe condition. 5. 6. If after performing steps 1-4 and the control is not functioning properly, verify the water level controls operation as outlined in “WATER LEVEL CONTROLS” under “ELECTRICAL OPERATION”. After checking the above items, if the low level cut off or differential water level control does not appear to be functioning as described, then replace the control and check for proper operation. 2. If lime scale build up is evident on the probe, thoroughly clean it removing all deposits from the probe and insulator. Do not use any thing abrasive on the insulator; use a soft cloth. 3. Inspect the probes for a cracked or damaged insulator. If a probe appears to be damaged, replace it with a new one and proceed to step 5. If a probe does not appear to be damaged then proceed to step 4. 4. Check through the probe socket opening in the top of the canister assembly for the presence of water. Water must drain from the probe canister and if in doubt, pour water into the canister and observe that it drains quickly. If water fails to drain from the canister, remove the cover or canister assembly and clean. 5. Reverse procedure to install and check for proper operation. CYCLING AND HIGH LIMIT PRESSURE SWITCHES (GAS AND ELECTRIC MODELS) WARNING: THE FOLLOWING STEPS REQUIRE POWER TO BE APPLIED TO THE UNIT DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES. Remove the boiler control box cover as outlined under “CYCLING AND HIGH LIMIT PRESSURE SWITCHES (GAS AND ELECTRIC MODELS)” to access the two controls. The pressure switch on the right is the cycling or primary control; the one on the left is the high limit control. They are identical switches, differing only in their settings. Turn the power ON and let the boiler come up to pressure. Close and seal one of the compartment doors, set a time past 5 minutes on the cooking timer, pull the steam control arm handle forward and turn the compartment power switch ON to exhaust pressure from the boiler. Observe boiler pressure gauge readings for several cycles and compare them with the pressure settings in the chart. If the readings differ, adjust the pressure settings as described below. Water Level Probes WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. 1. Remove the cover over the water level probes and disconnect the lead wire from each probe. Note the location of each probe and the number of the wire connected to it. Remove each water level probe for examination. Page 25 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS Two slotted and square headed adjustment screws extend through the top of the switch case. A pressure scale and indicating pointers are visible through the sight glass window to indicate the approximate pressure setting. The adjustment screw directly above the right side pointer changes the cut-out (off) set point and the adjustment screw directly above the left side pointer changes cut-in (on) set point. Adjust the screw to obtain the proper cut-out (off) setting first, then adjust the other screw to obtain the proper cut-in (on) setting. Turn the screw clockwise to increase the pressure setting and counterclockwise to decrease the pressure setting. The pressure settings for each switch are listed below. BOILER PRESSURE SETTINGS (PSI) CYCLING CONTROL TYPE HIGH LIMIT VL MODELS ON OFF ON 1. Remove the coil assembly from the valve stem by lifting up on the retaining cap at the top of the solenoid valve and sliding the metal cover plate off. 2. Clamp the body of the valve in a vise. 3. Mark a scribe line on the stem nut to the valve body for proper retightening. 4. Remove the stem locking nut to remove the stem from the valve body. 5. All parts are now accessible for inspection and cleaning. NOTE: If internal solenoid parts appear to be damaged or worn, then replace the solenoid valve. Do not reuse damaged or worn parts. No internal solenoid parts are available as a service replacement. OFF PS With Compartment Pressure Regulating Valve AS 9 11 6 15 4 6 2 15 A. Check rubber seal on bottom of plunger. B. Check plunger spring. C. Check O-ring in valve body. D. Check ports in valve body. SS MS With-Out Compartment Pressure Regulating Valve AS SS MS FILL AND COLD WATER SOLENOID VALVES 6. WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. Check to assure the solenoid valve is receiving power. If the solenoid valve is receiving power but the valve is not opening, the coil may be malfunctioning. Replace the solenoid valve and check for proper operation. If the solenoid valve is receiving power and the valve appears to be opening but little or no water is flowing through it, then the valve ports may be clogged with debris or a valve component malfunctioning. To check solenoid valve further, follow the procedure outlined below. Disassembly NOTE: It is recommended that the valve be removed for cleaning as outlined in this procedure. This will prevent damage to the lines and fittings when the stem is removed from the body. Reverse procedure to install. COMPARTMENT PRESSURE ADJUSTMENT Remove the left side panel from the boiler base to access the compartment pressure regulating valve. If the steamer is equipped with the compartment pressure regulating valve and the steamer is operating, set the pressure regulating valve to read 6 psi on the compartment gauge. Turn the hex head screw at the top clockwise to increase the pressure and counterclockwise to decrease. If the steamer is not equipped with the compartment pressure regulating valve, then the compartment will cycle at the same pressures of the boiler. A mechanical pressure relief valve serves as a safety backup control and is pre-set for a maximum of 8 psi. Page 26 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS HIGH LIMIT THERMOSTAT WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. Remove thermostat (bi-metallic disk type) as outlined under “HIGH LIMIT THERMOSTAT” in “REMOVAL AND REPLACEMENT OF PARTS”. Inspect the temperature sensing side of thermostat for corrosion or rust. Clean mounting and thermostat surfaces before remounting or replacing. A good metal-to-metal contact is essential for proper functioning of the thermostat. This service must be performed at least once a year. If thermostat mating surface can not be throughly cleaned or is severely pitted and rusted, then replace and check for proper operation. BOILER NOT FILLING WITH WATER Ensure that water to the steamer is turned on, then turn power switch ON. After approximately 10 minutes, if no water is observed in the water level gauge sight glass, then check for a problem with the boiler fill solenoid valve, water level control(s) or the water level probes. See “WATER LEVEL CONTROL TEST”. Also, ”water hammering” in the supply line, in conjunction with a check valve can cause a high water pressure pocket in the water line to the fill solenoid valve. The fill solenoid valve will not be able to overcome this pressure and operate to supply the boiler with water. Shut off the water supply and relieve the pressure in the line. Turn the water supply back on and check for proper operation. NOTE: To eliminate this problem, the customer must install a “water hammer suppression device” in the supply line to the boiler. WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. Scalants may be covering the water level control probe giving a false indication of a sufficient water level in the boiler. Remove and thoroughly clean the water level probes to remove scalants and lime build up. Also, Check through the probe socket opening in the top of the canister assembly for the presence of water. Water must drain from the probe canister and if in doubt, pour water into the canister and observe that it drains quickly. If water fails to drain from the canister, remove the cover or canister assembly and clean. These conditions indicate extremely poor water quality being supplied to the boiler and/or boiler clean out and deliming has not been performed. The water condition must be cleared up immediately with a proper water conditioner to avoid further problems with the steamer. Re-install the water level probes and canister assembly (if applicable). Perform a boiler inspection, clean-out and deliming procedure as outlined under “BOILER”. Check for proper operation. Water may be draining through an open boiler blowdown solenoid valve as quickly as it’s fed to the boiler. Loose wiring, a burned out coil or particles of scale trapped in the valve seat may prevent the valve from closing. Newer steamer models use a plunger type rod that raises and lowers to permit steam/water flow out of boiler. If debris has accumulated around the water orifice, the plunger may not seat properly to close off the opening. If this symptom is suspect, remove the solenoid as outlined in “FILL AND COLD WATER SOLENOID VALVES”. Remove any debris found on sealing surfaces, reassemble and install. If the solenoid valve still does not function properly, replace it with a new valve and check for proper operation. Older steamer models have a movable blade and when closed, the blade reacts as a guillotine that should be free to move fully down into the valve pocket (projection at bottom of valve) so that the pierced hole in the blade aligns perfectly with the body opening. If debris has accumulated in the bottom of the valve pocket, then the blade will not move into the pocket completely. If this symptom is suspect, remove the solenoid as outlined in “FILL AND COLD WATER SOLENOID VALVES”. NOTE: On this valve body, remove the two assembly bolts holding the brass body together and remove the loose internal parts. Remove any debris found on sealing surfaces, reassemble and install. If the solenoid valve still does not function properly, replace it with a new valve and check for proper operation. BOILER BLOWDOWN DRAIN SOLENOID VALVE The water contained in the boiler, being under pressure, should be blown through this valve and be noticeably visible exhausting out the steamer drain. Daily boiler blowdown is essential to proper operation and component life by removing sediment and scalants that may be lodged in the chamber of the boiler. Page 27 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS If the blowdown operation appears to function sluggishly or not at all, considerable scalants may be lodged in the drain pipe and/or the valve. Disconnect the valve from the drain line and inspect both the valve and the drain pipe fixed to the boiler. If considerable scalants or lime build up is apparent, then not only the valve, but also the boiler and water level probes must be thoroughly cleaned. See “FILL AND COLD WATER SOLENOID VALVES” for an inspection and cleaning procedure of a solenoid valve and "BOILER” for a procedure on boiler inspection, clean out and deliming. 1. If your steamer has an automatic blowdown drain valve. A. VL TYPE MODELS With Compartment Pressure Regulating Valve HIGH LIMIT ON OFF ON OFF 9 11 6 15 4 6 2 15 AS SS MS With-Out Compartment Pressure Regulating Valve Are equipped with normally open solenoid valves that close when energized by the main power switch. When the main power switch is turned off, the solenoid valve is deenergized and the boiler blowdown valve re-opens. 1. AS SS MS All Models (With Boiler) A. Check for low water pressure input, line strainer clogged or fill solenoid valve malfunction. See “FILL AND COLD WATER SOLENOID VALVES”. B. Boiler blowdown solenoid valve may be clogged and not fully closing. Check for a slow leak out of steamer drain. If not able to verify, then proceed to step 1C. If blowdown solenoid valve appears to be functioning properly, then proceed to step 1D. Turn the power switch(s) OFF and press the blowdown timer button. This activates the boiler blowdown timer and energizes (opens) the solenoid valve. Timer operates approximately four minutes then shuts off. C. Turn power switch OFF, disconnect lead wires from blowdown solenoid and remove it for inspection. D. A heavy build-up of scalants has possibly coated the interior of the boiler. The insulating effect of the scalants hampers heat transfer. Unbolt and remove the hand hole cover plate and gasket assembly. Examine interior of boiler and if scalants and/or lime build up is apparent, perform a boiler inspection, clean-out and deliming procedure. See “BOILER”. If considerable scalants are evident, then both the boiler blowdown solenoid valve and the water level probes must also be examined. If your steamer has a manual blowdown drain valve. A. CYCLING PS Older Models 1) 2. CONTROL Newer Models 1) B. NORMAL OPERATING STEAMER PRESSURES (PSI) Turn the power switch(s) OFF then open the valve to blowdown the boiler. Close the valve at the end of the blowdown sequence so boiler will be ready to fill. BOILER SLOW TO PRESSURIZE 2. If the boiler requires more than 15 minutes (20 minutes for regenerated models) to achieve normal operating pressure as listed in below, then check the following conditions. Page 28 of 88 Gas Models A. Low incoming gas pressure causes reduced BTU output. Check incoming line and manifold gas pressures as outlined in “GAS MANIFOLD PRESSURE ADJUSTMENT.” B. Gas combination control valve malfunction. Check incoming and manifold gas pressures as outlined in “GAS MANIFOLD PRESSURE ADJUSTMENT.” If pressure adjustments are made and manifold pressure remains low, replace the combination valve and check for proper operation. VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS C. D. 3. One or more electric heating elements malfunctioning. See “HEATING ELEMENTS” B. One or more heater contactors not pulling in to power heating elements. C. If steamer operates under three phase power, then check line for all phases. D. 5. Gas orifice clogged or obstructed around air shutter. It is possible for debris to become lodged in the small gas orifice opening over time. Clean-out the gas orifice using a round metal instrument of the same hole diameter or slightly smaller. Clean as needed. If clogging reappears, the orifice should be removed, cleaned and reinstalled. Remove any other foreign objects that appear to be obstructing the gas orifice or air shutters. INLET WATER STRAINER The in-line Y strainer should be located upstream of the fill valve solenoid. Shut off the water supply. Unscrew the cap from the body on the leg of the Y that should be pointing downwards toward the floor. Remove the screen and any foreign particles trapped in the opening. Rinse the screen thoroughly to remove accumulated debris and replace the screen in the valve body. If screen can not be thoroughly cleaned, replace it with a new one. Reinstall the cap and ensure that the Y strainer is positioned with the cap pointing downward to catch debris. The pressure regulating valve strainer will become clogged if dirty steam lines are connected to direct steam models. Remove the hex nut on the bottom of the pressure regulating valve to clean the strainer and valve seat. PILOT AND THERMOCOUPLE ASSEMBLY (GAS MODELS) Electric Models A. 4. Gas burner ports clogged or obstruction around air shutter. After a period of time, gas burners can accumulate carbon in their ports or become clogged by food and grease debris from kitchen cleaning, restricting performance. To clean burners, remove them from burner box and boil in water for 10 -15 minutes to dislodge clog. Clean-out any remaining debris from the gas ports using a wire brush, scribe or pic type metal instrument. Remove any other foreign objects that appear to be obstructing the gas ports or air shutters. Heavy scale build up on heating element causes reduced heating. Direct Steam Models A. Building steam supply pressure low. B. Cooking compartment steam solenoid valve malfunction. C. Steam pressure regulator adjusted too low. D. Clogging in the steam line reduces steam supply. Regenerated (Steam Coil) Steamers A. Heavy scale build up inside copper steam coil. B. Building steam supply pressure low C. Cooking compartment steam solenoid valve malfunction. WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. WARNING: SHUT OFF THE GAS BEFORE SERVICING THE UNIT. The pilot thermocouple when heated, supplies a DC millivolt signal to an internal solenoid valve on the gas combination control valve. This solenoid valve is designed to shut off the gas flow to the pilot and main burners in case of a malfunction in the system. When energized by the thermocouple voltage, the valve is held in the open position to permit gas flow. The pilot burner flame is controlled by an adjustable needle valve located under a small cap screw on the combination control valve. When experiencing pilot outages, visually check pilot flame for the proper contact on thermocouple and the flame color. Also, check to see that excessive air drafts are not interfering with proper heating of the thermocouple by the pilot flame. The pilot flame should be a steady blue flame that envelopes the thermocouple tip. The flame should be about one inch long with half its length extending beyond the outer edges of the pilot shield. If the pilot flame does not appear to be this length and color, then adjust as necessary. See the diagram below for an example of unsatisfactory pilot flames. Turn clockwise to decrease pilot flame and counterclockwise to increase. Page 29 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS NOTE: If adjustments in gas or pilot pressure settings are made, always replace the adjustment cover screw to assure proper gas control operation. Check the thermocouple output voltage as follows: 1. Turn the power switch OFF and disconnect the thermocouple from the gas combination control valve. 2. Check the thermocouple DC millivolt output with a VOM. If a meter is not available, replace the thermocouple with a new one and check operation again. A. Install a thermocouple adaptor into the connection on the gas combination control valve. Screw the thermocouple in to the adaptor then connect the meter leads to it. See “TOOLS” under “GENERAL” for information on thermocouple adaptor. If a thermocouple adaptor is not available then turn the power switch OFF, disconnect the thermocouple from the gas combination control valve and proceed to step 2D. B. Turn the power switch ON and light the pilot. Allow the pilot to heat the thermocouple for one to two minutes and take a closed circuit reading. Compare the readings with the chart below. If the adjustment does not result in a pilot flame of proper size, then gas might not be flowing properly to the pilot. Check for a plugged pilot orifice, a kinked or plugged pilot gas supply tube and for low gas supply pressure. The pilot operates unregulated at gas supply pressures while the pressure regulator in the combination control valve regulates pressure to the main burners only. Visually check the thermocouple tip (hot end) and tube lead for kinks or pinches that might be causing a short between the tube and the wire inside. Also, check the threaded connector tip for corrosion, tarnish or dirt which can cause a poor connection. If the thermocouple shows either of these signs, it should be replaced with a new one. NOTE: The connection of the tubing from the thermocouple tip to the control valve is an electrical connection and must be clean. Do not use any sealing compound on the threads or over tighten the threaded connection. Finger tighten the nut plus 1/4 turn with a wrench. Over tightening the nut could crush the insulator, shorting the thermocouple. If the pilot flame is correct and there are no drafts, then the problem is in the thermocouple output voltage or the gas solenoid valve in the combination control. Page 30 of 88 C. 1) If the reading is less than the minimum or thermocouple is not operating as described, replace the thermocouple as outlined under “PILOT AND THERMOCOUPLE ASSEMBLY (GAS MODELS)” in “REMOVAL AND REPLACEMENT OF PARTS” then check for proper operation. 2) If the reading is within the range listed in the chart below then thermocouple is operating properly. Reconnect the thermocouple to the gas combination control valve. 3) If after replacing thermocouple, the pilot or main burners are still not functioning properly, then a problem in the gas combination control valve exists as well. Replace the combination control valve as outlined under “GAS COMBINATION CONTROL VALVE” in “REMOVAL AND REPLACEMENT OF PARTS” then check for proper operation. Turn the power switch OFF and disconnect the thermocouple adaptor from the gas combination control valve and thermocouple. VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS D. With the thermocouple disconnected, connect the meter leads to the tube and threaded end. Turn the power switch ON and light the pilot. Hold down the OFF/PILOT/ON knob and allow the pilot to heat the thermocouple for one to two minutes. Take an open circuit reading and compare with the chart below. 1) 3. 3. Loosen the set screw on the burner being adjusted. Closing the air shutter will decrease primary air to the burner and opening the shutter will increase primary air the burner. 4. Monitor the burner flame and set the air shutter opening as follows: A. If the reading is less than the minimum or thermocouple is not operating as described, replace the thermocouple as outlined under “PILOT AND THERMOCOUPLE ASSEMBLY (GAS MODELS)” in “REMOVAL AND REPLACEMENT OF PARTS” then check for proper operation. If after checking and/or replacing thermocouple, the pilot or main burners are still not functioning properly, then a problem in the gas combination control valve exists as well. Replace the combination control valve as outlined under “GAS COMBINATION CONTROL VALVE” in “REMOVAL AND REPLACEMENT OF PARTS” then check for proper operation. NOTE: Gas combination control valves are not serviceable and should not be disassembled. Once you have isolated the problem to this control, replace it. Do not attempt to repair the assembly. THERMOCOUPLE DC MILLIVOLT READINGS CLOSED CIRCUIT (CONNECTED) Typical 15 Range 10 - 20 OPEN CIRCUIT (DISCONNECTED) Open up the air shutter until the inner portion (blue) of the flame lifts off the burner port and then turn the air shutter back until the flame touches the burner port again. A slight tinge of orange and yellow in the flame is acceptable. An extremely yellow flame indicates too little primary air (oxygen), producing poor burning characteristics and the heating efficiency drops off. A by product of this would be soot (carbon). Factory air shutter settings are: natural gas - open approximately ½ inch; propane gas - fully open. 5. After the air shutter adjustment is made, tighten the set screw. Inspection Remove gas burners by lifting burner up and sliding it to the rear just enough to clear the gas orifice hood. Lower the front end of burner and bring it forward under the gas manifold pipe. Inspect burner for clogged or damaged ports. Clean or replace as necessary. When reinstalling burners, assure that locating pin is in the hole for proper positioning and to prevent burner from rolling over. AUTOMATIC IGNITION SYSTEMS (GAS MODELS) 20 - 35 When the main power switch is turned ON and the ignition control modules reset switch is in the ON position, the ignition control module is energized with 24VAC between terminals five and six. GAS BURNERS The main gas burners are located under the boiler for heating and number five to seven depending on the steamer model. They are made of aluminized steel with lanced type ports and have adjustable air shutters in the front. Fixed orifice type hoods extend from the manifold to establish gas flow to each burner. High voltage is sent from terminal nine to the spark electrode and an output of 24 volts is sent from terminals two and three to the pilot coil in the combination valve, allowing gas to flow to the pilot. The sparking will continue for 90 seconds or until the flame sensor has confirmed that an adequate pilot flame is present. Air Shutter Adjustment 1. Ignite the burners and allow to heat up for at least five minutes. 2. Verify the manifold pressure as outlined under “GAS MANIFOLD PRESSURE ADJUSTMENT”. Page 31 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS Once the pilot flame is confirmed, a 24 volt output from terminal one will be sent, allowing the main valve (cycling) coil of the combination valve to operate at the request of the cycling pressure switch. A. Check to ensure that all electrical terminal connections on the ignition control module and the ignitor are clean and tight. If loose connections are found, make the necessary adjustments. B. Verify that the ignition control module and the ignitor have good ground wire connections. The ignitor mounting bracket should have good metal to metal contact to its mounting surface. C. Remove the pilot ignitor and check the following: 1) The gap between the spark probe and the ground clip should be approximately 1/8 inch. If the gap appears to be excessive or poor sparking is occurring then adjust. 2) Inspect the ceramic flame rod insulator for cracks or evidence of exposure to extreme heat, which can permit leakage to ground. If either of these conditions exist, then replace the pilot ignitor and re-test. 3) Check the ignition cable for tightness or damaged insulation. If the ignition cable appears to be damaged, then replace it and re-test. Terminals: 1. Main Valve - 24VAC will be present on terminal #1 with the pilot sensing electrode sensing an adequate pilot fame. This output will remain present as long as the pilot flame remains adequate. 2. Common (MV/PV). 3. Pilot Valve - 24VAC will be present on terminal #3 at the instant an input voltage is supplied to the module. This voltage will remain present on terminal #3 providing an adequate pilot flame is established within 90 seconds. In the event that an adequate pilot flame is not established within 90 seconds this output voltage will drop out. 4. Ground (burner). 5. 24VAC Neutral (ground). 6. 24VAC Input. 7. High Voltage to spark electrode (The pilot flame current is sensed by the Ignitor Module via the spark electrode high voltage wire and terminal #9). 2. A. Spark Ignition Control Test 1. Install the pilot ignitor and attach ignition cable. If the ignition control module does not appear to be sparking to ignite gas, perform the following: Page 32 of 88 Turn the main power switch ON and verify the ignition control modules re-set switch is ON. Observe spark condition from ignitor. 1) If a spark from ignitor is present and ignites the gas from the pilot and burner then the system is working properly. VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS 2) 3) 3. 4. If a spark from ignitor is present but does not ignite gas before the ignition control module locks out, (90 sec.) there may not be enough gas in the line for ignition. Verify the gas supply and gas combination control valve are both on. Turn the ignition control modules re-set switch OFF then ON to reset the module. Sparking should then resume to ignite gas. The module may need reset several times before ignition takes place. After the burner lights, compare the manometer pressure reading to the pressure chart near the end of this procedure. 4. If ignitor is still not sparking proceed to step 3. A. If other appliances are connected to the same gas line, turn them all ON and check manometer pressure reading again. If the pressure drops ½ inch water column or more, then the incoming pressure should be checked. then the gas supply needs to be checked by the gas line installer or the local gas company for adequate sizing. B. If no other gas appliances are connected to the gas line or the pressure does not drop as described above but the manifold pressure still requires adjustment, proceed to step 5. Check the ignition control module and transformer. A. Turn the ignition control modules re-set switch OFF then ON to eliminate a lockout condition. B. Check for 24VAC output on the ignition control module transformer. 1) If 24VAC is present between terminals 5 & 6 on the ignition control module but ignitor is not sparking, then replace ignition control module and re-test. 2) If 24VAC is not present then ensure that transformer is receiving 120VAC input. If ignition control module transformer is receiving proper voltage, then replace ignition control module transformer and re-test. After making the necessary component adjustments or replacements, check for proper operation. 5. Remove the adjustment screw cap to access the pressure adjustment screw. 6. After the burner lights, set the pressure as outlined below. GAS MANIFOLD PRESSURE ADJUSTMENT WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. A. To increase pressure, turn the screw clockwise. B. To decrease pressure, turn the screw counterclockwise. NOTE: Accurate gas pressure adjustments can only be made with the gas ON and the burner lit. PRESSURE READINGS (INCHES W.C.) WARNING: SHUT OFF THE GAS SUPPLY BEFORE SERVICING THE UNIT. LINE 1. Open the front cabinet doors and turn the gas combination control valve off. 2. To measure the manifold pressure, remove the 1/8 inch NPT plug (pressure tap) on the outlet side of the valve and attach a manometer. 3. Turn the gas combination control valve and the main power switch to ON. GAS TYPE MANIFOLD RECOMMENDED MIN Natural 4.0 7.0 5.0 Propane 10.0 11.0 11.0 MAX 14 NOTE: If the incoming line pressure is less than the minimum stated, then the manifold pressure can not be set correctly. Page 33 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS 7. 8. Once the correct pressure has been set, turn the power switch OFF, replace the adjustment screw cap and 1/8 inch NPT plug (pressure tap) on the outlet side of the valve. Check for proper operation. DIRECT STEAM MODELS HEATER CONTACTORS WARNING: DISCONNECT THE ELECTRICAL POWER TO THE MACHINE AT THE MAIN CIRCUIT BOX. PLACE A TAG ON THE CIRCUIT BOX INDICATING THE CIRCUIT IS BEING SERVICED. The contactor can be serviced by removing the cover of the contactor box. These models consist of a pressure regulator and gauge that run off a buildings potable steam supply. The regulator used will be of the adjustable type and should be set for a discharge pressure of 10 psi. The maximum input pressure to the regulator should be 15 psi. Incoming power (120VAC) for the compartment controls is supplied from a junction box in the base. REGENERATED STEAM (OLDER MODELS) A noisy contactor (hum or chatter) is generally due to excessive dust or dirt on the armature pole faces or around the armature core preventing the magnet coil from pulling the armature into a completely sealed position. This can usually be corrected by blowing or wiping the pole faces clean. To inspect electrical contacts, remove cover at top of contactor by removing two screws which hold it in place. Replace contactor if the electrical contacts appear to be severely pitted or burned. HEATING ELEMENTS The steam coils on a regenerated type steamer are intended for use at a steam supply pressure of 15 psi maximum. A pressure regulating valve is available as optional equipment for steamers where a buildings steam supply pressure exceeds 15 psi. The regulator used will be of the adjustable type and should be set for a discharge pressure high enough for good steam generation. This pressure can be monitored by the supplied pressure gauge. The regulator should be set, only when steam is flowing (steam solenoid valve is open). If steam is heavy with condensate, install a ball float trap in the steam line before the pressure regulating valve. WARNING: THE FOLLOWING STEPS REQUIRE POWER TO BE APPLIED TO THE UNIT DURING THE TEST. USE EXTREME CAUTION AT ALL TIMES. 1. Measure the voltage at the heating element terminals and verify it against the data plate voltage. A. If voltage is incorrect, find the source of the problem. B. If voltage is correct, check current draw (amps) through the heating element lead wires. See table below for proper values. C. If current draw is correct then heating element is ok. D. If current draw is not correct then replace the element and proceed to step 3. WARNING: SHUT OFF THE STEAM SUPPLY BEFORE SERVICING THE UNIT. To remove a steam coil, disconnect union in steam supply line to the coils and in the condensate discharge line from the coils. Remove header that supplies steam to coils by disconnecting union at each coil. In same way, remove coil condensate collection header. Remove four bolts clamping each coil flange in place and pull coil forward. Use a new flange gasket when replacing coil. The faces that mate with gasket must be clean. Turn steamer power switch ON, allowing steam generation and, consequently, pressure to rise to normal operating level and then turn power switch OFF for a final purging of boiler and steam supply lines. Steamer is now ready for use. NOTE: When replacing an element, always use a new gasket and ensure that the flange and tube surfaces which contact the gasket are clean. If removed element shows a pronounced scale build-up on its heating tubes, the other elements should be removed and mechanically cleaned to remove the scale. This will prolong their life. DO NOT immerse elements in a chemical solution to descale. 2. Page 34 of 88 Check for proper operation. VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS NUMBER KW TOTAL OF PER VOLTAGE KW ELEMENTS ELEMENT AMPERAGE PER LINE 1 PH 3 PH RESISTANCE PER ELEMENT (OHMS) 208 18 2 9 87 50 14.42 240 18 2 9 75 44 19.20 480 18 2 9 22 76.80 *220/380 240/415 18 2 9 25 19.20 208 24 2 12 116 68 10.82 240 24 2 12 100 58 14.40 480 24 2 12 29 57.60 *220/380 240/415 24 2 12 34 14.40 208 36 4 9 100 14.42 240 36 4 9 87 19.20 480 36 4 9 44 76.80 *220/380 240/415 36 4 9 50 19.20 208 42 4 10.5 117 12.36 240 48 4 12 116 14.40 480 48 4 12 58 57.60 *220/380 240/415 48 4 12 67 14.40 NOTES: 1. Values in the table are nominal. Tolerance is +/-10 %. 2. Asterisk (*) indicates 3 phase/4wire. 3. Each heater has three internal elements. Page 35 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS THERMAL SWITCH - PREVENT AND AUTOMATIC MODELS D. If the cooking cycle is started normally, but the red light and timer do not come on or an abnormal amount of time elapses before they come on, then the load compensator is set too high. Also, if the timer stops, the red light goes out, and the buzzer does not sound after the compartment has exhausted the steam or if the time is set as usual for the product and the product is overcooked or if the time is set as usual for the product and the product is overcooked. E. If there is too short a time between starting and the red light coming on, or if it comes on immediately, the load compensator is set too low. Also, if the time is set as usual for the product and the product is undercooked. The load compensator is a thermal switch in a stainless steel housing that screws into a 3/8 NPT fitting (newer models) on the left side wall of the compartment. The switch contacts should close when the compartment temperature reaches 180(F, supplying power to the steam exhaust solenoid valve, pilot light and cooking timer motor. 1. Newer Models A. 2. This switch is NON-ADJUSTABLE. Check to see if the switch is operating properly as described below. If the switch is suspected to be malfunctioning, replace it and check for proper operation. Older Models A. The switch can be adjusted by turning the slotted screw. Turn the screw clockwise to lower the closing temperature and counterclockwise to raise the closing temperature. Check the operation of the switch as described below. These models are ½ NPT. The correct adjustment or verification of the load compensator can best be made by using a digital thermometer and thermocouple to sense the compartment temperature. WATER LEVEL GAUGE ASSEMBLY 1. Close the valve at the top and at the bottom of the gauge assembly. 2. Unscrew the packing nuts at the top and bottom of the glass tube. 3. Slide the glass tube upwards, until the bottom of the tube is clear of the fitting and lift it out. 1. Position the thermocouple near the exposed bulb of the load compensator inside the compartment. 4. Reinstall the tube and use new sealing washers. Do not over tighten the packing nuts, it could break the gauge glass. 2. Close and seal the compartment. Pull the steam control arm handle forward, set the timer and turn the compartment power switch ON. 5. Open the top and bottom valves fully. 6. Check for proper operation. 3. Monitor the thermocouple temperature, and adjust or verify (as applicable) the load compensator temperature. A. The red light of the compartment switch should light when the thermocouple reads 185 ±7 (F. B. After the cooking cycle ends and the compartment temperature lowers, the thermal switch should then re-open at 165 ±7 °F. C. If the load compensator can not be adjusted correctly or the temperature is out side the allowable limits, then replace thermal switch and check for proper operation. Page 36 of 88 VL SERIES STEAMER - SERVICE PROCEDURES AND ADJUSTMENTS STEAM GATE VALVE(S) On all models, each cooking compartment has its own mechanical steam gate valve that supplies steam to the cooking compartment when the steam control arm handle is pulled forward. The Prevent models use a solenoid valve to exhaust steam from the compartment whereas the Automatic, Standard and Manual models use an additional steam gate valve to exhaust steam when the steam control arm handle is returned to the rear. These gate valves are a standard type and can be disassembled for cleaning and gasket replacement. If steam leaks are noticed around the packing nut and stem during cooking, tighten the packing nut until the steam leak ceases. Release steam control arm to ensure its automatic return. If arm does not return freely or steam is still leaking, then further inspection or adjustments are necessary. Turn the timer and compartment power switch OFF and blowdown the boiler. Remove the control arm bracket and packing nut from the stem and clean out the old string packing. The valve stems may then be re-packed using a string packing suitable for steam service. Replace the packing nut and control arm bracket. Tighten the packing nut finger tight plus ½ turn and check for proper operation. If steam continues to leak, tighten the packing nut in additional ½ turn increments until it stops and re-check operation of the steam control arm. NOTE: Do not over tighten packing glands, the linkage system must be free enough for the spring to return the steam control arm to the fully closed position. For other service to these valves, remove the stem assembly and cap at the top of the valve. Check the valve linkage for loose or binding parts. The steam gate valve linkage for these controls are simple and there function easily seen. The inlet and exhaust steam gate valves must be positioned so the inlet valve is open and the exhaust valve closed when the steam control arm handle is pulled forward and reverses when the control arm is released. NOTE: In the event of an electrical component or a power failure, the steam control arm can be operated manually on automatic models. Page 37 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION ELECTRICAL OPERATION WATER LEVEL CONTROLS Solid State - Low level Cut-Off & Differential Control The steamer is equipped with three water level sensing probes (high, low and low level cut-off) and a single water level control board. The water level control board performs two functions: 1. Provide low level cut-off protection to shut off the heat source in case the water level drops below the low level cut-off (LLCO) probe. 2. When the water level drops below the low level (LL) probe, power is removed from the inverse latching relay, the HL relay energizes through ILR-2 and HL contacts change state. The fill solenoid is energized through HL-3 to refill the boiler and the HL LED is lit. The HL relay and LED will toggle ON and OFF during a cooking cycle as needed. Performs as a differential level control to maintain the water level between the low and high water level probes. The water level control (WLC) has input voltage (120VAC) across terminals 11 and 12 which powers the transformer. On one side of the transformer secondary, power is provided to the control by a series path through chassis ground (terminal 10). The other side of the transformer secondary (12VAC) supplies power to one side of the internal relays LLCO, HL and ILR. As water enters the boiler, it becomes part of the water level control’s circuit. When the water level in the boiler reaches a probe, that circuit is completed. The inverse latching relay of the board is deenergized, leaving the ILR-1 (N.O.) and ILR-2 (N.C.) contacts in their shelf state. When the main power switch is turned ON, power is supplied to the WLC board which energizes the high level (HL) relay and illuminates the HL relay LED. With the HL-3 contacts closed, the boiler fill solenoid is energized and water begins filling the boiler. When the water level reaches the low level cut-off (LLCO) probe, the LLCO relay is energized and illuminates the LLCO LED. With the LLCO-2 contacts closed the heat source is then energized. The LLCO relay will remain energized and its LED will stay lit until the water level in the boiler drops below the LLCO probe. When the water level reaches the low level (LL) probe, power to terminal 2 on the WLC board is present but no switching occurs. After the water level reaches the high level (HL) probe, the inverse latching relay of the board is energized and locked through the low level probe (LL) and ILR-1 contacts. With ILR-2 contacts open, this de-energizes the HL relay and the HL LED goes out. With the HL-3 contacts open, the boiler fill solenoid is de-energized, stopping the flow of water into the boiler. Page 38 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Solid State - Auxiliary Low Level Cut-Off This control serves as a safety backup to the main water level control (WLC) board to meet Cal-Code and CSD-1 code requirements. The auxiliary control provides auxiliary low level cut-off protection to shut off the heat source in case the water level drops below the low level cut-off (LLCO) probe. A single LLCO probe is connected to the auxiliary control. When the boiler stops filling, press the manual reset button on the boiler control box. On CSD-1 models, this energizes the low water relay, turns off the low water light and energizes the heat source auxiliary control. On Cal-Code models, this closes and locks the manual reset switch contacts to energize the heat source auxiliary control. The auxiliary water level control (WLC) has input voltage (120VAC) across terminals L1 and L2 to power the transformer primary. On one side of the transformer secondary, power is provided to the control by a series path through chassis ground. The other side of the transformer secondary (12VAC) supplies power to one side of the internal relay LLCO. As water enters the boiler, it becomes part of the auxiliary water level control’s circuit. When the water level in the boiler reaches the LLCO probe, the circuit is completed. When the main power switch is turned ON, power is supplied to the auxiliary WLC board but no switching occurs. On CSD-1 models, the low water level indicator light (amber) on the boiler control box comes on. When the water level reaches the low level cut-off (LLCO) probe, the LLCO relay is energized and illuminates the LLCO LED. With the LLCO-2 contacts closed the auxiliary heating control is then energized. The LLCO relay will remain energized and its LED will stay lit until the water level in the boiler drops below the LLCO probe. Page 39 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Electro Mechanical - Low level Cut-Off & Differential Control The steamer is equipped with three water level sensing probes (high, low and low level cut-off), a differential level control (1G1GO) and a low level cut-off control (1D1DO). The low-level cut-off is an additional control that is identical to the differential level control but serves as the safety backup to shut off the heat source in case the water level drops below the low level cut-off (LLCO) probe. The differential level control maintains the water level between the low and high water level probes. Each control is powered by input voltage (120VAC) on terminals 1 and 2 which also connect to the primary side of the internal transformer. The transformer secondary (300VAC) will provide power to the internal contactor coil through a series path going from one side of the secondary winding, through the contactor coil, through the water level control probe, through the water in the boiler and to the boiler for ground. The other side of the transformer secondary is attached to ground. When the main power switch is turned ON, both water level controls are energized. The boiler fill solenoid is then energized through the normally closed contacts (terminals 3 & 4) on the differential level control and water begins filling the boiler. When the water level reaches the low level cut-off (LLCO) probe, the internal contactor coil on the low water level control is energized. With the contacts on terminals 7 & 8 now closed, the heat source is then energized. The internal contactor coil will remain energized until the water level in the boiler drops below the LLCO probe. When the water level reaches the low level (LL) probe, power to terminal 7 on the differential level control will be present but no switching occurs. After the water level reaches the high level (HL) probe, the differential control contactor coil is energized and the normally closed contacts on terminals 3 & 4 open, which de-energizes the boiler fill solenoid and stops the flow of water into the boiler. The internal contactor coil will have a locking path through contacts 7 & 8 to the low level probe to keep the coil energized after the water level drops below the high level probe. When the water level drops below the low level (LL) probe, the internal contactor coil is de-energized, returning contacts 3 & 4 back to their normally closed state and energizing the boiler fill solenoid to refill the boiler. The water level must then fill to the high level probe again, to energize the internal contactor coil. The differential control will toggle ON and OFF during a cooking cycle as needed. Page 40 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Electro Mechanical - Auxiliary Low Level Cut-Off This control serves as a safety backup to the main low level cut-off (LLCO) control to meet Cal-Code requirements. The operation of the auxiliary control is identical to the main low level cut-off control but performs a single function: 1) Provide auxiliary low level cut-off protection to shut off the heat source in case the water level drops below the low level cut-off (LLCO) probe. A single LLCO probe identical to the LLCO probe on the main low level cut-off control is connected to the auxiliary control. The auxiliary control is powered by input voltage (120VAC) on terminals 1 and 2 which also connect to the primary side of the internal transformer. The transformer secondary winding (300 VAC) will provide power to the internal contactor coil through a series path going from one side of the secondary winding, through the contactor coil, through the water level control probe, through the water in the boiler and to the boiler for ground. The other side of the transformer secondary is attached to ground. When the main power switch is turned ON, the auxiliary low level control is energized but no switching occurs. When the water level reaches the low level cut-off (LLCO) probe, the internal contactor coil on the low level control is energized, closing the contacts on terminals 7 & 8. The internal contactor coil will remain energized until the water level in the boiler drops below the LLCO probe. When the boiler stops filling, press the manual reset button on the boiler control box. This closes and locks the manual reset switch contacts to energize the heat source auxiliary control. Page 41 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION SEQUENCE OF OPERATION GAS MODELS This sequence of operation is written for steamers with electronic ignition, solid state water level controls, CSD-1 (code) boiler controls option and with Prevent cooking compartment controls. Refer to schematic diagram numbers 3928 and 3929 for a boiler control schematic and 3962 for a schematic and wiring diagram on Prevent cooking compartment controls. NOTE: The high pressure indicator light will remain on and the safety circuit de-energized until boiler steam pressure is within operational limits (high limit pressure switch closed) and the manual reset button is pressed. The low water indicator light will remain on and the safety circuit de-energized until the water level in the boiler reaches the low level cut-off probes (minimum level) for the water level control, the auxiliary low level cut-off control and the manual reset switch is pressed. The gas burners will not light until these conditions are satisfied. D. Initial Fill and Preheat 1. 1) High level (HL) relay is energized, HL-3 (N.O.) contacts close and HL LED lights up. 2) The inverse latching relay of the board remains de-energized, leaving the ILR-1 (N.O.) and ILR-2 (N.C.) contacts in their shelf state. Conditions. A. Power switch OFF. B. Ignition module reset switch ON C. Cooking timers off. D. Compartment power switches OFF. E. Unit connected to correct voltage . 1) 2) 2. Water level control (WLC) is powered. L1 (HOT) to one side of the cooking compartment controls; to one side of the cold water condenser thermostat; to one side of the power ON/OFF switch. L2 (NEUTRAL) to one side of the cooking compartment controls; to one side of the cold water condenser (CWC) solenoid valve; to one side of the power ON/OFF switch. F. Unit properly grounded. (Boiler and water level control share a common ground) G. Water supply valve on. H. Gas supply valve on. I. Gas combination control valve ON. J. Control (cycling) pressure switch closed. K. High limit pressure switch closed. L. Cold water condenser (CWC) thermostat open. M. Blowdown solenoid valve (drain) open and boiler empty. N. Compartment doors open. Power switch turned ON. (located on boiler control box) A. Power switch indicator light (red) comes on. B. Hi pressure indicator light (amber) comes on. C. Low water level indicator light (amber) comes on. E. Auxiliary low water level cut-off control is powered, LLCO-2 (N.O.) contacts remain open. F. With the HL-3 and ILR-2 contacts closed, the fill solenoid is energized and water boiler begins filling. G. Blowdown solenoid valve is energized and closes. H. Ignition module begins sparking to light pilot after a 3 second delay. 1) If pilot ignition is established (pilot lit) then a micro amp flame sense current is sent back to the ignition control module through the ignition cable. Sparking stops, pilot remains lit and is ready to ignite burners. 2) If pilot ignition is not established after 90 seconds, sparking stops and the ignition control module locks out power to the combination gas valve (pilot valve and main valve remain closed). The module remains locked out until the reset switch on the ignition control module box is switched to OFF then ON to re-start the ignition trial cycle. NOTE: If the modules re-set switch is in the OFF position, no sparking will occur or if it’s turned OFF while idling or cooking, then pilot and burners will go out and not re-ignite upon call for heat by the cycling pressure switch. Page 42 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION 3. C. Water level reaches LLCO (low water level cutoff) probe for the water level control and to the auxiliary LLCO probe for the auxiliary low level cut-off control. A. Power to terminal 9 on the water level control. 1) B. D. LLCO relay energizes, LLCO-2 (N.O.) contacts close and LED lights. Power to terminal LLCO on the auxiliary low water level cut-off control. 1) E. 7. LLCO relay energizes, LLCO-2 (N.O.) contacts close and LED lights. NOTE: LLCO relays will remain energized and LLCO LED’S will remain lit until the water level drops below the LLCO probes or the power switch is turned OFF. 4. 5. A. Power to terminal 6 on water level control. 1) 6. A. Cycling pressure switch opens, main gas solenoid valve de-energizes, gas flow shuts off and burners go out. B. As boiler heats up and builds pressure, some by-pass water/steam is produced which runs into the steam drain box. This causes the cold water condenser (CWC) solenoid to cycle, cooling the drain water. This solenoid is powered by the CWC thermostat. Power to terminal 2 on the water level control is present but no switching occurs. Water reaches HL (high level) probe. The inverse latching relay of the board is energized, changing the state of ILR-1 (N.O.) and ILR-2 (N.C.) contacts. The inverse latching relay will remain energized through the alternate latching path of ILR-1 contacts until the water level recedes below the low level probe. 2) With ILR-2 contacts open, HL relay is de-energized, HL-3 (N.O.) contacts open and HL LED goes out. 3) Water fill solenoid is de-energized. (boiler fill time approx. 11 min.) NOTE: Steam should not be seen entering a compartment until the manual steam control arm is pulled forward and locked. 8. Boiler steam pressure drops below lower limit set point of 9 PSI and the cycling pressure switch closes. Manual re-set switch is pressed, energizing the coils on the high limit and low water relays. A. Contacts 1 & 9 on the high pressure relay change state and lock from N.C. to N.O. and turn off the high pressure indicator light. Concurrently, Contacts 1 & 9 on the low water relay change state and lock from N.C. to N.O. and turn off the low water indicator light. B. Contacts 5 & 9 on the high pressure relay change state and lock from N.O. to N.C., supplying power (NEUTRAL) to one side of the auxiliary gas solenoid valve. Concurrently, Contacts 5 & 9 on the low water relay change state and lock from N.O. to N.C., supplying power (L1) to the other side of the auxiliary gas solenoid valve. Burners light and water in boiler begins to heat up. Boiler steam pressure reaches upper limit set point of 11 PSI. (Approximately 15 min.) Water reaches LL (low level) probe. A. Auxiliary gas solenoid valve is energized and opens to allow gas flow. As long as the ignition control module is sensing a pilot flame, the internal main valve (MV) contacts close (N.O.) on the ignition control module. The main gas valve is energized and gas begins flowing. NOTE: For both relays to energize, the high pressure switch must be closed and the water level in the boiler must be above the low level cut-off probes in order for LLCO-2 (N.O.) contacts to close. Page 43 of 88 A. Boiler steam pressure is maintained by the cycling of the pressure switch between the upper and lower set point limits. The cycling pressure switch continues to energize and de-energize the main gas solenoid valve starting and stopping the flow of gas, which in turn, cycles the burners on and off. This sequence continues until one of the following occurs: 1) Boiler pressurizes to 15 PSI, causing the high limit pressure switch to open. At that time, the auxiliary gas valve de-energizes, shutting off the gas flow to the burners and the high limit failure light will come on. This light will stay lit until the pressure drops below the lower limit set point of 6 PSI and the manual re-set switch is pressed. 2) Boiler water level drops below the LLCO probes for the water level and the auxiliary low level cut-off controls which then de-energizes the LLCO relays, changing the contact state of LLCO-2 (N.O.) back to open. This deenergizes the main and auxiliary gas solenoid valves. The gas solenoid valves will remain off and the low water level light will come on and stay lit until the water level rises above the LLCO probes and the manual re-set switch is pressed. VL SERIES STEAMER - ELECTRICAL OPERATION A. Cook Cycle 1. A Cook cycle should not be started, until the initial fill and preheat is completed, in order for the boiler steam pressure to be within operational limits. A. Insert product into steamer. B. Compartment door is closed and screw handle tightened down. C. 4. Cooking timer is manually turned off. 5. Compartment power switch is turned OFF, buzzer is de-energized and power is removed from the common side of micro switch SW1. 6. Steamer reverts to preheat cycle until: Compartment steam control arm is pulled forward and latches, allowing steam to enter compartment. NOTE: Cool air and condensate exit through the steam exhaust solenoid valve (N.O.) until compartment temperature reaches 180°F. D. 2) E. Micro switch SW1 contacts change state from N.C. to N.O. Micro switch SW2 contacts also change state from N.C. to N.O. Compartment power switch is turned ON. 1) L1 (HOT) to one side of the thermal switch. NOTE: L2 (NEUTRAL) is connected to the other side of the buzzer, steam exhaust solenoid valve, trip solenoid, pilot light and timer motor. F. Once compartment temperature reaches approximately 180°F thermal switch closes and supplies power L1 (HOT) to: 1) B. Water level drops below low level cut-off probe. C. Power switch is turned OFF. Steam exhaust solenoid valve (N.O.) energized and closes. NOTE: The cold water condenser thermostat remains closed and cold water condenser solenoid stays energized while cooking. If main water is shut off after boiler fill, then no cold water is present to condense steam/hot water and steam vapors exit the floor drain. Water Refill (After Initial Fill) 1. 2) Pilot light (red) comes on indicating timed cooking at 180°F has started. 3) Timer motor energized Water level drops below low level probe (LL). A. B. Micro switch SW2 contacts change state from N.O. back to N.C. (normal starting position). 1) 2) Steam exhaust solenoid valve is deenergized and opens to exhaust steam and pressure from the compartment. Power is removed from terminal 2 on the water level control . 1) Cooking Timer times down to approximately one minute before zero. A. 3. A cooking cycle is started. i.e. compartment door is closed and screw handle tightened down, time is dialed into timer (past 5 minutes) and the compartment power switch is turned ON. NOTE: Burners will re-light after the boiler pressure drops below the low pressure set point limit (9 psi) and will stay on until the high pressure set point (11 psi) is reached. As long as steam pressure is within limits, even while cooking, burners can go off. The boiler is able to re-pressurize to the upper set point limit even with all compartments in cook mode. NOTE: Even though steam exhaust solenoid valve is closed, a small opening exists in the “guillotine” blade of the valve to allow “limited free venting” of condensate during a cook cycle. 2. A. Time is dialed on timer (past 5 minutes). 1) Micro switch SW1 contacts change state from N.O. back to N.C. (normal starting position).. 2. Steam trip solenoid is energized and unlatches steam control arm allowing it to return to the rear. Steam supply the compartment is shut off. Cooking timer reaches zero. Page 44 of 88 HL relay is energized. 1) Contacts HL-3 close. 2) HL LED comes on. 3) Fill solenoid is energized and water flows into tank. Water reaches LL (low level) probe. A. 3. The inverse latching relay is deenergized, returning ILR-1 (N.O.) and ILR-2 (N.C.) contacts back to their original state. Power to terminal 2 on the water level control is present but no switching occurs. Water reaches high level probe. A. The inverse latching relay of the water level control is energized, changing the state of ILR-1 (N.O.) and ILR-2 (N.C.) contacts. B. HL relay is de-energized. VL SERIES STEAMER - ELECTRICAL OPERATION 4. 2) 1) HL-3 opens. 2) Fill solenoid de-energized and water stops flowing into tank. 3) HL LED goes out. The water refill cycle will occur whenever the water level is below the low level probe and will not affect the operation of either the preheat or cook cycle. L2 to the common terminal on the blowdown timer relay; to pin 4 on the boiler ON/OFF switch; to one side of the manual reset switch; to one side of the auxiliary switch(s) mounted on the side of the auxiliary contactor(s); to the compartment controls. F. Unit properly grounded. (Boiler and water level control share a common ground) Boiler Blowdown/drain G. Water supply valve on. 1. Main power switch turned OFF. H. Control (cycling) pressure switch closed. A. Boiler blowdown sequence starts. I. High limit pressure switch closed. B. The blowdown solenoid valve (N.O.) is deenergized and valve opens to drain the boiler. J. Cold water condenser (CWC) thermostat open. K. C. Power is removed from all components except cold water condenser (CWC) thermostat and solenoid valve. The CWC thermostat cycles as necessary to lower the discharge temperature of the water and condense steam going into the drain. Blowdown solenoid valve (drain) closed and boiler empty. L. Compartment doors open. 2. Power switch turned ON. (located on boiler control box) A. Power to terminal 2 on the differential water level control then jumpers connect to terminal 2 on both the low level cut-off and auxiliary low level cut-off water level controls. B. Power switch indicator light (red) comes on. C. Boiler fill solenoid valve is energized and boiler begins to fill. ELECTRIC MODELS This sequence of operation is written for steamers with electro mechanical water level controls, CalCode boiler controls option and with Prevent cooking compartment controls. Refer to schematic diagram number 3941 for a boiler control schematic and 3962 for a schematic and wiring diagram on Prevent cooking compartment controls. INITIAL FILL AND PREHEAT 1. NOTE: The safety circuit remains de-energized until the water level in the boiler reaches the low level cut-off probe (minimum level) for the auxiliary low level cut-off control and the manual reset switch is pressed. Also, until the water level in the boiler reaches the low level cut-off probe (minimum level) for the low level cut-off control, the low level cut-off control remains de-energized. The heating elements will not come on until the manual rest switch is pressed these conditions are satisfied. Conditions. A. Power switch OFF. B. Manual reset switch OFF. C. Cooking timers off. D. Compartment power switches OFF. E. Unit connected to correct voltage supply. 1) L1 to one side of the boiler fill solenoid valve; to one side of the main and auxiliary contactor(s); to one side of the power on light (red); to one side of the heat on light (amber); to one side of the timer motor; to one side of the cold water condenser solenoid valve; to one side of the blowdown solenoid valve; to terminal 1 on the auxiliary low level control then jumpers connect L1 to terminal 1 on the differential and low level controls; to the compartment controls. 3. Page 45 of 88 Water level reaches LLCO (low water level cutoff) probe for the low level cut-off control and to the auxiliary LLCO probe for the auxiliary low level cut-off control. A. Power to terminal 10 on the low level cutoff and on the auxiliary low level cut-off control is present. The internal contactor coil on the water level controls are then energized. 1) The normally open contacts on terminals 7 and 8 for both the main and auxiliary low level cut-off controls close. 2) The main heater contactor(s) are then energized. VL SERIES STEAMER - ELECTRICAL OPERATION 1) NOTE: Power the internal contactors on the low level cut-off and auxiliary low level cut-off will remain, until the water level drops below the LLCO probes or the power switch is turned OFF. 4. Manual reset switch is pressed (momentary). A. The auxiliary heater contactor is energized supplying power to the heating elements and the heat light (amber) comes on. 1) B. Internal relay on manual reset switch is energized. 1) 5. Normally open contacts close and lock to provide power to the auxiliary heater contactor and the heat light after the reset switch is released. Water reaches LL (low level) probe. A. 6. Water in boiler heats up. Power to terminal 7 on the differential level control is present but no switching occurs. COOK CYCLE 1. Water reaches HL (high level) probe. A. Power to terminal 10 on the differential level control. 1) The internal contactor coil on the differential level controls is energized. a. The normally closed contacts on terminals 3 and 4 open, deenergizing the boiler fill solenoid and the boiler stops filling. NOTE: The internal contactor coil has a locking path through contacts on terminals 7 & 8 to the low level probe to keep the coil energized after the water level drops below the high level probe. 7. Boiler steam pressure reaches upper limit set point of 11 PSI. (Approximately 15 min.) A. Cycling pressure switch opens, heater contactor(s) de-energize and power to the heating elements is removed. A Cook cycle should not be started, until the initial fill and preheat is completed, in order for the boiler steam pressure to be within operational limits. A. Insert product into steamer. B. Compartment door is closed and screw handle tightened down. C. Compartment steam control arm is pulled forward and latches, allowing steam to enter compartment. NOTE: Cool air and condensate exit through the steam exhaust solenoid valve (N.O.) under “Full Free Venting” until the compartment temperature reaches 180°F. When the solenoid valve energizes and closes, condensate will continue to exhaust through a small opening the valve under “Limited Free Venting” until the solenoid valve de-energizes and re-opens, one minute before the end of a cook cycle. D. NOTE: Steam should not be seen entering a compartment until the manual steam control arm is pulled forward and locked. 8. Boiler steam pressure drops below lower limit set point of 9 PSI and the cycling pressure switch closes. A. Boiler pressurizes to 15 PSI, causing the high limit pressure switch to open. At that time, the auxiliary heating element contactor(s) are deenergized, shutting off power to the heating elements. The pressure switch will remain open until the pressure drops below the lower limit set point of 6 PSI. Boiler water level drops below the LLCO (low water level cut-off) probes for the low level cut-off and the auxiliary low level cutoff controls, de-energizing the internal contactor on both controls. This deenergizes the main and auxiliary heater contactors, shutting off power to the heating elements. The heating elements will remain off until the water level rises above the LLCO probes and the manual re-set switch is pressed. Boiler steam pressure is maintained by the cycling of the pressure switch between the upper and lower set point limits. The cycling pressure switch continues to energize and de-energize the heating element contactor(s), which in turn, cycles the heating elements on and off. This sequence continues until one of the following occurs: Page 46 of 88 E. Time is dialed on timer (past 5 minutes). 1) Micro switch SW1 contacts change state from N.C. to N.O. 2) Micro switch SW2 contacts also change state from N.C. to N.O. Compartment power switch is turned ON. 1) L1 (HOT) to one side of the thermal switch. NOTE: L2 (NEUTRAL) is connected to the other side of the buzzer, steam exhaust solenoid valve, trip solenoid, pilot light and timer motor. VL SERIES STEAMER - ELECTRICAL OPERATION F. Once compartment temperature reaches approximately 180°F thermal switch closes and supplies power L1 (HOT) to: 1) WATER REFILL (AFTER INITIAL FILL) 1. Water level drops below low level probe (LL). A. Steam exhaust solenoid valve (N.O.) energized and closes. 1) NOTE: Even though steam exhaust solenoid valve is closed, a small opening exists in the “guillotine” blade of the valve to allow “limited free venting” of condensate during a cook cycle. 2) 3) 2. Micro switch SW2 contacts change state from N.O. back to N.C. (normal starting position). Steam exhaust solenoid valve is deenergized and opens to exhaust steam and pressure from the compartment. 2) Steam control solenoid (trip) is energized and unlatches steam control arm allowing it to return to the rear. Steam supply the compartment is shut off. Micro switch SW1 contacts change state from N.O. back to N.C. (normal starting position). B. Buzzer is energized. a. The normally closed contacts on terminals 3 and 4 open, deenergizing the boiler fill solenoid and the boiler stops filling. NOTE: The internal contactor coil has a locking path through contacts on terminals 7 & 8 to the low level probe to keep the coil energized after the water level drops below the high level probe. 1. Cooking timer is manually turned off. 5. Compartment power switch is turned OFF, buzzer is de-energized and power is removed from the common side of micro switch SW1. 6. Steamer reverts to preheat cycle until: C. The internal contactor coil on the differential level controls is energized. The water refill cycle will occur whenever the water level is below the low level probe and will not affect the operation of either the preheat or cook cycle. BOILER BLOWDOWN/DRAIN 4. B. Power to terminal 10 on the differential level control. 1) 4. A. Power to terminal 2 on the water level control is present but no switching occurs. Water reaches HL (high level) probe. A. 1) The internal contactor coil is deenergized returning contacts 3 and 4 back to there original state and energizing the boiler fill solenoid to refill the boiler. Water reaches LL (low level) probe. A. 3. Cooking timer reaches zero. A. 2. Timer motor energized Cooking Timer times down to approximately one minute before zero. A. 3. Pilot light (red) comes on indicating timed cooking at 180°F has started. Power is removed from terminal 7 on the differential water level control. Main power switch turned OFF. A. 2. A cooking cycle is started. i.e. compartment door is closed and screw handle tightened down, time is dialed into timer (past 5 minutes) and the compartment power switch is turned ON. Water level drops below low level cut-off probes. Power switch is turned OFF. NOTE: Heating elements will come back on, after the boiler pressure drops below the low pressure set point limit (9 psi) and will stay on until the high pressure set point (11 psi) is reached. As long as steam pressure is within limits, even while cooking, heating elements can go off. The boiler is able to repressurize to the upper set point limit even with all compartments in cook mode. Page 47 of 88 Power switch indicator light (red) goes out and power is removed form all boiler controls except the blowdown timer. Blowdown timer switch is pressed. A. The normally open timer contacts close, energizing the blowdown solenoid valve and the cold water condenser valve. B. Boiler begins blowing down and draining until timer “times out” after approximately 4 minutes. C. Timer contacts re-open and power is then removed from the blowdown solenoid valve and the cold water condenser valve. VL SERIES STEAMER - ELECTRICAL OPERATION PAGE PURPOSELY LEFT BLANK Page 48 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION SCHEMATICS, GAS STEAMERS, BOILER CONTROLS VL2G AND VL3G - PREVENT, AUTOMATIC, STANDARD AND MANUAL Manual Ignition, Standard Controls Page 49 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Electronic Ignition, Standard Controls Page 50 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Manual Ignition, CSD-1 Code Controls Page 51 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Electronic Ignition, CSD-1 Code Controls Page 52 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 53 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION WIRING DIAGRAMS, GAS STEAMERS, BOILER CONTROLS VL2G AND VL3G - PREVENT, AUTOMATIC, STANDARD AND MANUAL Manual Ignition, Standard Controls Page 54 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 55 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Electronic Ignition, Standard Controls Page 56 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 57 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Manual Ignition, CSD-1 Code Controls Page 58 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 59 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Electronic Ignition, CSD-1 Code Controls Page 60 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 61 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION SCHEMATICS, ELECTRIC STEAMERS, BOILER CONTROLS VL2E AND VL3E - PREVENT, AUTOMATIC, STANDARD AND MANUAL Auto Blowdown, Standard Controls Page 62 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Auto Blowdown, Cal-Code Controls Page 63 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION WIRING DIAGRAMS, ELECTRIC STEAMERS, BOILER CONTROLS VL2E AND VL3E - PREVENT, AUTOMATIC, STANDARD AND MANUAL Auto Blowdown, Standard Controls (contactor - 1 std.) Page 64 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 65 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Auto Blowdown, Standard Controls (contactors - 2 std.) Page 66 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 67 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Manual Blowdown, Cal-Code Controls (contactors - 1 std. 1 aux.) Page 68 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 69 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Auto Blowdown, Cal-Code Controls ( contactors - 1 std. 1 aux.) Page 70 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 71 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Auto Blowdown, Cal-Code Controls (contactors - 2 std. 2 aux.) Page 72 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 73 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Manual Blowdown, Cal-Code Controls (contactors - 2 std. 2 aux.) Page 74 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Page 75 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION WIRING DIAGRAMS, ELECTRIC HEATER CIRCUITS VL2E AND VL3E - PREVENT, AUTOMATIC, STANDARD AND MANUAL Standard and Cal-Code/CSD-1 Controls Page 76 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION SCHEMATIC AND WIRING DIAGRAMS, DIRECT STEAMERS, CABINET BASE VL2D AND VL3D - PREVENT, AUTOMATIC, STANDARD AND MANUAL See “SCHEMATIC AND WIRING DIAGRAMS - COMPARTMENT CONTROLS” Page 77 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION WIRING DIAGRAMS, REGENERATED STEAMERS, BOILER CONTROLS VL2R AND VL3R - PREVENT, AUTOMATIC, STANDARD AND MANUAL Manual Blowdown (Older Models) Page 78 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Auto Blowdown (Older Models) Page 79 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION SCHEMATIC AND WIRING DIAGRAMS - COMPARTMENT CONTROLS Prevent Page 80 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Automatic Page 81 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Standard Page 82 of 88 VL SERIES STEAMER - ELECTRICAL OPERATION Manual NO ELECTRICAL COMPONENTS ARE USED WITH THE MANUAL COMPARTMENT CONTROLS OPTION. THE CONTROLS CONSIST OF A MANUAL COOKING TIMER AND MANUAL STEAM CONTROL ARM TO CLOSE AND OPEN THE STEAM GATE VALVES. Page 83 of 88 VL SERIES STEAMER - TROUBLESHOOTING TROUBLESHOOTING ALL MODELS WARNING: CERTAIN PROCEDURES IN THIS SECTION REQUIRE ELECTRICAL TESTS OR MEASUREMENTS WHILE POWER IS APPLIED TO THE MACHINE. EXERCISE EXTREME CAUTION AT ALL TIMES. IF TEST POINTS ARE NOT EASILY ACCESSIBLE, DISCONNECT POWER, ATTACH TEST EQUIPMENT AND REAPPLY POWER TO TEST. SYMPTOM Compartment leaks water around door. Cold water condenser not operating properly. POSSIBLE CAUSES 1. Drain screen clogged. 2. Drain line obstructed or not to an open gap drain. 3. Steamer not level. 4. Excessive cooking compartment pressures. A. On models equipped with the compartment pressure regulating valve, verify the compartment pressure is 6 psi during cooking. If pressure is higher then adjust the pressure regulating valve and re-check. See COMPARTMENT PRESSURE ADJUSTMENT” in “SERVICE PROCEDURES AND ADJUSTMENTS”. B. On models with out the compartment pressure regulating valve, verify the compartment pressure is 6 psi during cooking. If pressure is higher then adjust the cycling pressure switch and re-check. See “CYCLING AND HIGH LIMIT PRESSURE SWITCHES (GAS AND ELECTRIC MODELS)” in “SERVICE PROCEDURES AND ADJUSTMENTS”. 1. Water supply not on. 2. Plugged spray nozzle. 3. Cold water condenser solenoid inoperative or plugged. 4. Cold water condenser thermostat malfunction or needs adjustment. 5. No power to cold water condenser solenoid. 1. Compartment door not properly sealed. 2. Worn or damaged gasket. 3. Drain line obstructed or not to an open drain. Steam generated inside compartment when timer or compartment power switch is OFF. 1. Steam gate valve not fully closing (clogged, dirty or malfunctioning). See “STEAM GATE VALVE” in “SERVICE PROCEDURES”. Heat coming on without water in boiler (Dry firing). 1. Lime scale (moist) on LLCO water level probe or probe damaged (shorted to ground). 2. Retention of water in probe canister assembly. 3. Water level control malfunction. 1. Pressure relief valve malfunction. 2. Cycling pressure switch set to high. See “CYCLING AND HI LIMIT PRESSURE SWITCHES (GAS AND ELECTRIC MODELS)” in “SERVICE PROCEDURES”. Steam leaks around door. Pressure relief valve opening or leaking. Page 84 of 88 VL SERIES STEAMER - TROUBLESHOOTING SYMPTOM Boiler base will not heat or build pressure. POSSIBLE CAUSES 1. Check incoming voltage. 2. Boiler not filled - check fill solenoid for power, clogging or malfunction. 3. Water Level Control malfunction. HL-3 relay not energizing or contacts not closing to power boiler fill solenoid. 4. Water too “pure” for probes to properly conduct electricity. 5. Contactor malfunction (electric only). 6. Heating element inoperative (electric only). 7. Cycling pressure switch open or set too high. Steamer is cycling on high limit. 8. High limit thermostat open. 9. Problem with auto blowdown timer (older models). 10. Power switch malfunction. 11. Pressure reducing valve malfunction or needs cleaned (direct or regenerated models only). 12. Low or no steam supply to steamer (direct or regenerated models only). Steam output low or slow cooking. Boiler leaks water. Boiler fill solenoid cycling to frequently. Boiler water level too high. Boiler does not fill or slow to fill. 1. Steam gate valve not fully opening or blocked. 2. Cycling pressure switch malfunction or needs adjustment. 3. Steam header line (supply) blockage. 4. Heavy amount of condensate in the pressure controls steam supply line. 5. Pressure relief valve leaking. 6. Steam supply lines leaking. 1. Loose water, steam or drain line connections (top or base). 2. Boiler hand hole gasket not sealing. 3. Leak at gauge glass. 1. LL probe lime scaled over (dry) or damaged and not sensing water. 2. Water level control malfunction. 1. Fill solenoid does not shut off. 2. High level probe lime scaled over (dry) or damaged and is not sensing water (open circuit). 3. Water level control malfunction. HL-3 relay not de-energizing or contacts not opening. 1. Water supply not on or pressure too low. 2. Line strainer clogged. 3. Fill solenoid not malfunctioning or plugged. 4. A High pressure pocket in the supply line to the boiler causes the fill solenoid valve not to open. See ”BOILER NOT FILLING WITH WATER” in “SERVICE PROCEDURES AND ADJUSTMENTS”. 5. Water level control malfunction. HL-3 relay not energizing or contacts not closing to power boiler fill solenoid. Page 85 of 88 VL SERIES STEAMER - TROUBLESHOOTING SYMPTOM Cooking timer motor does not run. POSSIBLE CAUSES 1. Timer not getting power. 2. Timer motor inoperative. 1. Cooking timer malfunction. 2. Buzzer malfunction. Compartment red light and timer do not come on; excessive time elapses before they come on; timer stops, the red light goes out, and the buzzer does not sound after compartment exhausts steam; time is set as usual for the product and the product is overcooked. 1. Thermal switch (load compensator) is set too high. Short a time between starting and the red light coming on; red light comes on immediately; time is set as usual for the product and the product is undercooked. 1. Thermal switch (load compensator) is set too low. Cooking Compartment Controls inoperative 1. Ensure that voltage is reaching control circuit through compartment power switch when turned ON. 2. On electric heat models with a transformer, check step down transformer (located in the contactor box) for proper operation. 3. Check cooking timer function and contact position. See “SCHEMATIC AND WIRING DIAGRAMS COMPARTMENT CONTROLS” under “ELECTRICAL OPERATION”. 4. Check that timer motor operates when connected to power. If a problem is found in timer, replace it, do not take timer apart. 5. On prevent and automatic models check the load compensator for malfunction. 6. Check wiring for damaged insulation. (no short circuit) 7. Check that all connections and terminals are securely fastened. (no open circuits) 8. Check that all connections are made according to compartment control wiring diagram. 1. Steam control arm not returning after unlatching (automatic, standard and manual models). Buzzer not operating. Cooking Compartment not venting at end of cook cycle (Prevent models) or when manual steam control arm is released. 2. A. Broken or missing return spring. B. Packing nut on steam gate valve to tight. C. Steam control (trip) solenoid malfunction (prevent and automatic models). Steam exhaust solenoid valve malfunctioning (prevent models). Page 86 of 88 VL SERIES STEAMER - TROUBLESHOOTING GAS MODELS ONLY SYMPTOM Burner won’t light. POSSIBLE CAUSES 1. Gas not on. 2. Ignition control module reset switch in the OFF position or malfunctioning. 3. Ignition module not receiving power. Check ignition module transformer for 24VAC output to module on automatic ignition systems. 4. Steamer not properly grounded and/or polarity of incoming power is incorrect on automatic ignition systems. 5. Low incoming gas pressure. See “GAS MANIFOLD PRESSURE ADJUSTMENT” in “SERVICE PROCEDURES”. 6. Ignition module malfunction. 7. Gas combination control valve malfunction. 8. Boiler not filling. Check fill solenoid for power, clogging or malfunction. 9. Water level control malfunction. HL-3 relay not energizing or contacts not closing to power boiler fill solenoid. 10. Water too ”pure” for probes to properly conduct electricity. 11. High limit thermostat open (if equipped). 12. High limit pressure switch open. 13. Cycling pressure switch open or set too high. Steamer is cycling on high limit. See “CYCLING AND HI LIMIT PRESSURE SWITCHES (GAS AND ELECTRIC MODELS) in SERVICE PROCEDURES”. Burner won’t stay lit. 1. Gas pressure low. See “GAS MANIFOLD PRESSURE ADJUSTMENT” in “SERVICE PROCEDURES”. 2. Check gas orifice for obstruction. 3. Ignition module malfunction. Page 87 of 88 VL SERIES STEAMER - TROUBLESHOOTING SYMPTOM Pilot not lit or goes out. Spark Ignitor not sparking. Form 24650 (May 1999) POSSIBLE CAUSES 1. Gas not on. 2. Pilot going out due to drafts, excess steam from drain or steamer not level. Improper venting can direct the pilot flame away from thermopile or flame sensor. 3. Low incoming gas pressure. See “GAS MANIFOLD PRESSURE ADJUSTMENT” in “SERVICE PROCEDURES”. 4. Pilot not adjusted correctly. See “PILOT AND THERMOCOUPLE ASSEMBLY (GAS MODELS)” in “SERVICE PROCEDURES AND ADJUSTMENTS”. 5. Check thermopile millivolts. See “PILOT AND THERMOCOUPLE ASSEMBLY (GAS MODELS)” in “SERVICE PROCEDURES AND ADJUSTMENTS”. 6. Burners ignite too violently. Check gas pressure to the steamer. See “GAS MANIFOLD PRESSURE ADJUSTMENT” in “SERVICE PROCEDURES”. 7. If auto ignition and no sparking - ignition module malfunction. 8. Wrong pilot assembly used. 1. Poor ground between pilot bracket and burner. 2. Loose, broken or damaged lead wires (including ground) from ignition module to ignitor. 3. Ignitor boot on ignition cable loose, damaged or missing causing excessive ignition voltage leakage. 4. Ceramic flame rod insulator on ignitor cracked or damaged from extreme heat. 5. Incorrect spark gap setting. See “AUTOMATIC IGNITION SYSTEMS (GAS MODELS)” in “SERVICE PROCEDURES”. 6. Ignition module not receiving power. Check to ensure the ignition control module reset switch is ON. 7. Ignition module malfunction. Printed in U.S.A.